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Exercise during pregnancy improves maternal health perception: a randomized controlled trial
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OBSTETRICS
Exercise during pregnancy improves maternal health perception: a randomized controlled trial Ruben Barakat, PhD; Mireia Pelaez, BSS; Rocio Montejo, MD, PhD; Maria Luaces, MD, PhD; Maria Zakynthinaki, PhD OBJECTIVE: We have studied the effect of moderate physical activity
that is performed by healthy women during their entire pregnancy on their perception of health status. STUDY DESIGN: Eighty sedentary women were assigned randomly to either an exercise group (n ⫽ 40) or a control group (n ⫽ 40). Maternal perception of health status and several pregnancy outcomes were recorded. RESULTS: Significant differences (P ⫽ .03) were found between study
groups in the percentage of women who perceived their health status as
“very good”; the values that corresponded to the exercise group (n ⫽ 18; 54.5%) were better than those of the control group (n ⫽ 9; 27.3%). In addition, the women of the exercise group gained less weight (11,885 ⫾ 3146 g) than those of the control group (13,903 ⫾ 2113; P ⫽ .03). CONCLUSION: A moderate physical activity program that is performed
over the first, second, and third trimester of pregnancy improves the maternal perception of health status. Key words: exercise, pregnancy, maternal health, weight gain
Cite this article as: Barakat R, Pelaez M, Montejo R, et al. Exercise during pregnancy improves maternal health perception: a randomized controlled trial. Am J Obstet Gynecol 2011;204:402.e1-7.
P
hysical exercise has gained increasing popularity among women of fertile age; many women ask for medical advice on whether they can continue to exercise throughout their pregnancy.1 The greater the number of pregnant women who want to participate in sports activities, the more important becomes the question about influence of exercise on mother and fetus.2 Historically, women have received various advice regarding a better pregnancy and labor. These were recommendations from different groups of profesFrom the Facultad de Ciencias de la Actividad Física y del Deporte – INEF, Universidad Politécnica de Madrid (Drs Barakat and Zakynthinaki, and Ms Pelaez); and the Hospital de Fuenlabrada (Drs Montejo and Luaces), Madrid, Spain. Received Aug. 17, 2010; revised Dec. 21, 2010; accepted Jan. 18, 2011. Reprints: Maria Zakynthinaki, PhD, Instituto de Ciencias Matemáticas, CSIC - UAM - UC3M UCM, c/ Serrano 121, 28006 Madrid, Spain. [email protected]. Authorship and contribution to the article is limited to the 5 authors indicated. There was no outside funding or technical assistance with the production of this article. 0002-9378/$36.00 © 2011 Mosby, Inc. All rights reserved. doi: 10.1016/j.ajog.2011.01.043
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sionals, religious leaders, philosophers, and doctors.3 However, when the physical and physiologic mechanisms and processes of pregnancy started to be understood, the advice to women regarding the type of the appropriate physical exercise during pregnancy became more precise.4 Despite the scientific findings, some questions still exist among the researchers regarding the influence of physical exercise on several aspects of pregnant women (ie, psychologic factors). A few studies have focused on the psychologic benefits on exercise during pregnancy.5,6 Pregnancy is a unique human process in which all the body control systems are modified to maintain maternal and fetal homeostasis.7 One of the most important changes during pregnancy is the metabolism of the mother, which results in a normal weight gain during pregnancy of approximately 9-11 kg.8 Any additional increase in the maternal weight is an energy reserve so that the mother can later feed her baby, but it also is a risk for maternal overweight, obesity, and complications to maternal health status.9 Obese women have increased possibilities of the development of future pelvic floor problems. This fact, combined with the increased frequency of complications during labor that are caused by
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obesity,10-12 puts these women in a group at special risk of poor quality of life.13 It should be noted here that pelvic floor problems (urinary and fecal incontinence, hyperactive bladder, pain during sexual relations, and pelvic prolapse) still remain a taboo subject. In many cases, these problems are thought erroneously to be the inherent consequence of having gone through labor. The reason for this is more cultural than scientific and seriously affects maternal perception of health status.14 Regular participation in exercise programs has been associated with primary and secondary prevention of numerous physical health problems.5 There is also strong evidence that moderate exercise results in a more positive self-concept, improved mental well-being, an enhanced sense of well-being, a higher quality of life, and an improved mood.15-17 When a pregnant woman exercises, her improved muscular strength may be beneficial especially in preventing back pain, may help in feeling agile and nimble, and may facilitate the added weight and the changing center of gravity.3 Also, recent studies in this area have shown that physical exercise during pregnancy plays an important role in the prevention of obesity and excessive weight gain and in control of the weight of women who
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www.AJOG.org are already obese; this can be achieved without any maternal-fetal risks, as far as pregnancy outcomes are concerned.18-21 The traditional recommendations regarding physical activity during pregnancy have been based more on cultural and social matters rather than scientific evidence.22,23 Even nowadays, doubts exist among both obstetricians and sport scientists regarding the type, the intensity, the duration, and the frequency of physical exercise during pregnancy and its influence on the maternal psychologic aspects. A more important aspect is the maternal perception of health status. Adequate research in this area of science is therefore necessary. This becomes even more obvious when one takes into account the fact that everyday more women want to continue to exercise in some form, during their pregnancy.22 The aim of this study was to investigate the influence of a program of moderate physical exercise during the entire pregnancy on maternal perception of health status and other pregnancy outcomes.
M ATERIALS AND M ETHODS The present study was a randomized, controlled training trial. We contacted a total of 360 Spanish (white) women in a low-to-medium socioeconomic class (the contact was made by the obstetrician during the first prenatal visit). From the initial number of pregnant women, finally 67 women were studied (Figure). The research protocol was reviewed and approved by our Ethics Committee and followed the ethical guidelines of the Declaration of Helsinki, which was last modified in 2008. The research was carried out in collaboration with the Obstetric Hospital Department (Hospital de Fuenlabrada, Madrid, Spain). All participants were informed about the aim and study protocol, and written informed consent was provided by all women. All exercises were carried out under the supervision of an obstetrician.
Subjects We randomly assigned (by use of a random number table) 80 healthy pregnant
women (age, 23-38 years) to either an exercise group (EG; n ⫽ 40) or a control group (CG; n ⫽ 40). Women not planning to give birth in the same obstetrics hospital department (Hospital de Fuenlabrada, Madrid, Spain) and not receiving medical follow-up evaluations throughout the entire pregnancy period were not included in the study. Both groups included subjects with similar prepregnancy level of physical activity or type of recreational exercise. All the women were healthy and had uncomplicated and singleton pregnancies. The exclusion criteria were any type of absolute obstetric contraindication to aerobic exercise during pregnancy,24,25 which included other contraindications that the authors considered to have a relevant influence on maternal perception of health: hemodynamically significant heart disease, restrictive lung disease, incompetent cervix/cerclage, multiple gestation, risk of premature labor, preeclampsia/pregnancy induced hypertension, thrombophlebitis, recent pulmonary embolism (last 5 years), acquired infectious disease, retarded interuterine development, serious blood disease, and/or absence of prenatal control.
Exercise program The physical conditioning program included a total of 35- to 45-minute weekly sessions 3 days each week (Monday, Wednesday, Friday) from the start of the pregnancy (weeks 6-9) to the end of the third trimester (weeks 38-39). Thus, an average of 85 training sessions was planned originally for each participant in the event of no preterm delivery. All subjects used a heart rate monitor (Accurex Plus; Polar Electro OY, Oulu, Finland) during the training sessions to ensure that exercise intensity was light-to-moderate (that is, their heart rate was consistently under 70% of their age-predicted maximum heart rate value [220 minus age]). Each session included a 25-minute core session that was preceded and followed by a gradual warm-up and cooldown period, respectively (both of 7-8 minute duration and consisting of walking and light, static stretching [avoiding muscle pain] of most muscle groups [upper and lower limbs, neck and trunk
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muscles]). The cool-down period also included relaxation and pelvic floor exercises. The core session included the following toning and very light resistance exercises: toning and joint mobilization exercises that included shoulder shrugs and rotations, arm elevations, leg lateral elevations, pelvic tilts, and rocks. Resistance exercises were performed through the full range of motion that normally is associated with correct technique for each exercise and engaged the major muscle groups (pectoral, dorsal, shoulder, upper and lower limb muscles). They included 1 set (10-12 repetitions of each) of abdominal curls and the following exercises with barbells (3 kg/exercise) or low-to-medium resistance bands (Therabands; The Hygenic Corporation, Akron, OH): biceps curls, arm extensions, arm side lifts, shoulder elevations, bench press, seated lateral row, lateral leg elevations, leg circles, knee extensions, knee (hamstring) curls, ankle flexion, and extensions. We specifically avoided any exercises that involved extreme stretching and joint overextension, ballistic movements or jumps. Any type of exercises on the back were performed for no more than 2 minutes.3,26 We used exercises that covered the major muscle groups of arms and abdomen to promote good posture and prevent low back pain and, in the third trimester, to strengthen the muscles of labor and pelvic floor.27 We also included in the program 1 session per week of aerobic dance. To maximize safety, adherence to the training program, and its efficacy, all sessions were supervised by a qualified fitness specialist (working with groups of 10 –12 subjects) and with the assistance of an obstetrician, were accompanied by music, and were performed in the hospital, in a spacious, well-lit room under favorable environmental conditions (altitude 600 m; temperature, 19-21°C; humidity, 50 – 60%). The following general considerations were given to the exercise program: All the activity was of aerobic type, and an adequate intake of calories and nutrients was assured before the start of the exercise program. As a general rule and to avoid potential risks, the following
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FIGURE
CONSORT 2010 flow diagram of the study participants
CONSORT, Consolidated Standards of Reporting Trials. Barakat. Exercise during pregnancy improves maternal health perception. Am J Obstet Gynecol 2011.
activities were avoided: activities that included Valsalva’s mechanism; high room temperatures or humid environments, with the aim to avoid chances of hyperthermia (body temperature, ⬎38°C); ballistics movements; and positions of extreme muscular tension. 402.e3
Variables of the study The following maternal characteristics have been taken into account: age, body mass index, smoking habits, alcohol intake, occupational activity, time standing per day, time of domestic task, educational level, and parity.
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The variables that are related to health perception and urinary incontinences were perception of health status level and frequency to pregnant women lose urine. The SF-36 King’s Health Questionnaire has been used.28-31 This test is a
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TABLE 1
Maternal characteristics Maternal characteristics Maternal age, y
a
Exercise group (n ⴝ 34)
Control group (n ⴝ 33)
P value
31 ⫾ 3
30 ⫾ 3
⬎ .05
23.9 ⫾ 3
24.8 ⫾ 4
.............................................................................................................................................................................................................................................. 2
Body mass index, kg/m
..............................................................................................................................................................................................................................................
⬎ .05
Smoking habits, n (%)
.....................................................................................................................................................................................................................................
Yes
3 (8.8)
6 (18.2)
No
23 (67.7)
22 (66.7)
8 (23.5)
5 (15.1)
..................................................................................................................................................................................................................................... .....................................................................................................................................................................................................................................
Before pregnancy, not now
..............................................................................................................................................................................................................................................
⬎ .05
Alcohol intake, n (%)
.....................................................................................................................................................................................................................................
Yes
1 (4)
3 (7)
No
33 (96)
30 (93)
..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
⬎ .05
Occupational activity, n (%)
.....................................................................................................................................................................................................................................
Sedentary job
14 (41.2)
14 (42.4)
Housewife
3 (8.8)
5 (15.2)
Active job
17 (50.0)
14 (42.4)
..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
⬎ .05
Standing, n (%)
.....................................................................................................................................................................................................................................
⬎3 h
19 (55.9)
13 (34.9)
⬍3 h
15 (44.1)
20 (60.6)
..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
⬎ .05
Domestic tasks, n (%)
.....................................................................................................................................................................................................................................
⬎2 h
12 (35.3)
16 (48.5)
⬍2 h
22 (64.7)
17 (51.5)
..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
⬎ .05
Education, n (%)
.....................................................................................................................................................................................................................................
⬍High school
3 (8.8)
6 (18.2)
High school
16 (47.1)
19 (57.6)
⬎High school
15 (44.1)
8 (24.2)
..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
Parity
.04
.....................................................................................................................................................................................................................................
0
26 (76.5)
12 (36.4)
1
8 (23.5)
20 (60.6)
⬎1
0
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The pregnancy outcomes that were considered were maternal weight gain, gestational age, type of delivery, delivery lacerations, blood pressure, 1-hour glucose tolerance, birthweight, and Apgar score.
Data analysis Our data were analyzed with the use of the Student t test for independent samples (Tables 1-3). A power analysis was conducted to determine the number of participants needed to reach a 2 value with an adequate level of statistical power. This analysis confirmed that adequate power (⬎ .80) with an 95% confidence level and a confidence interval of 10% (we allowed for 10% dropouts over 20 weeks) would be achieved with 40 pregnant women in the EG and with 40 pregnant women in the CG. We provide maternal characteristics of the study sample by groups (EG and CG) in terms of means and SDs, unless otherwise stated. For group comparisons of pregnancy outcomes, we analyzed continuous and nominal data with t test for unpaired data. We compared Apgar scores between groups using the nonparametric Mann-Whitney U test. Statistical analysis was performed with the Statistical Package for Social Sciences software (version 14.0 for Windows; SPSS Inc, Chicago, IL); the level of significance was set to ⬍ .05.
..................................................................................................................................................................................................................................... .....................................................................................................................................................................................................................................
1 (3.0)
.............................................................................................................................................................................................................................................. a
Data are expressed as mean ⫾ SD.
Barakat. Exercise during pregnancy improves maternal health perception. Am J Obstet Gynecol 2011.
multipurpose, short-form health survey with only 36 questions and yields an 8-scale profile of functional health and well-being scores, psychometrically based physical and mental health summary measures, and a preference-based health utility index. The CIQ-SF Incontinence classification of the International Continence Society has also been used.32 This test measures the subjective grade of urinary incontinence (regarding the patient) and its impact on quality of life.
Because the aim of the study was to observe the influence of exercise on the process of pregnancy and delivery, the questionnaires were given to the subjects after delivery. The study assumed that all participating subjects had started their pregnancy with the same (good) level of perception of their health status, which was confirmed during their first prenatal visit. Regarding incontinence problems, women who experienced such problems before pregnancy were excluded from the study.
R ESULTS Our results are presented in Table 1 (maternal characteristics), Table 2 (maternal perception of state of health and frequency of pregnant women to lose urine), and Table 3 (pregnancy outcomes). According to our analysis and regarding adherence to training and its possible adverse effects, we report that 6 women from the EG discontinued the intervention because of diagnosed risk for premature labor (n ⫽ 1), pregnancy-induced hypertension (n ⫽ 1), and personal reasons (n ⫽ 4). Seven participants of the CG were excluded from the study because of pregnancy-induced hypertension (n ⫽ 2), threat of premature delivery (n ⫽ 2), and personal reasons (n ⫽ 3). The final number of participants
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were 34 pregnant women in the EG and 33 pregnant women in the CG. There were no exercise-related injuries experienced during pregnancy. Adherence to training in the experimental group was 90%. No women changed from the CG to the EG or vice versa, and there were no protocol deviations from the study as planned. At the beginning of our study, we found no between-group differences regarding the potential confounding variables (such as occupational activities, standing, smoking habits, alcohol intake). Parity was the only exception; the EG presented a major percentage of nulliparaous women (76.5%) than did the CG (36.4%; P ⫽ .04). Regarding the perception that a pregnant woman has about her health status and the problems that are associated with her pelvic floor (incontinences), the women who performed a program of physical exercise reported a better health status than those who did not participate in any program (Table 2). In fact, although 18 women (54.5%) of the EG perceived that their health status was “very good,” the respective number of women in the CG was only 9 (27.3%; P ⫽ .03). Concerning incontinence perception of our study subjects, no significant differences between the study groups have been found, although the most prominent factor is surely the question of how frequently a pregnant woman has urine loss; in the CG, there were 3 women (9.1%) who reported “several times by day”; in the EG, there was only 1 woman (2.9%). As we show in Table 3, the pregnant women of the EG gained less weight (11,885 ⫾ 3146 g) than did the women in the CG (13,903 ⫾ 2113 g; P ⫽ .03). It should be noted that, according to our results, the weight gain of the pregnant women in the EG is considered normal for a healthy pregnancy. We found values moderately encouraging in the section of lacerations that were produced by the mechanics of the childbirth (Table 2); in laceration of type I, 8 women (24.2%) of the CG were reported vs 5 women of the EG (14.7%). 402.e5
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TABLE 2
Maternal perception of state of health and frequency of pregnant women to lose urine Variable
Exercise group (n ⴝ 34)
Control group (n ⴝ 33)
Maternal perception of health status, n (%)
P value .03
.....................................................................................................................................................................................................................................
Very bad
1 (3.0)
1 (3.0)
Some bad
0
5 (15.2)
..................................................................................................................................................................................................................................... .....................................................................................................................................................................................................................................
Good
14 (42.4)
18 (54.5)
Very good
18 (54.5)
9 (27.3)
..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
⬍ .05
Frequency of pregnant women to lose urine, n (%)
.....................................................................................................................................................................................................................................
Never
24 (70.6)
22 (66.7)
Once a week
5 (14.7)
5 (15.2)
2-3 times/week
2 (5.9)
1 (3.0)
Once a day
2 (5.9)
2 (6.1)
Several times a day
1 (2.9)
3 (9.1)
Continually
0
0
..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
Barakat. Exercise during pregnancy improves maternal health perception. Am J Obstet Gynecol 2011.
C OMMENT The aim of the present work was to study the possible effects of aerobic exercise during pregnancy on the perception of maternal health status, weight gain during pregnancy, and urinary incontinence. Our results showed an increased perception of health status in the EG (P ⫽ .03). This is in accordance with authors who reported physical activity as a factor to improve the perception of maternal health or health-promoting lifestyles.33 A number of authors reported that the physical exercise acts as an important factor to improve psychologic factors; most of these studies concern mood or stress level of a pregnant woman.34,35 Pregnancy is a period of important changes in all the body control systems that result in modifications in a woman’s psychologic status and the relevant emotional instability.3 The present study shows that a physical activity program could minimize these modifications and emotional complications and thus contribute to a healthy pregnancy. There is sufficient evidence that demonstrates that exercise during pregnancy (and during every other period of life) is beneficial not only regarding the physio-
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logic aspects but also regarding a woman’s perception of well-being.5,6 We believe that a program of moderate physical exercise during pregnancy not only can improve the maternal perception of health status but also can contribute to the strengthening of other emotional factors during pregnancy and after delivery. Specifically as related to the incontinences and the complications of pelvic floor, some researchers have presented programs of physical exercise that are dedicated only to the invigoration of the pelvic floor muscles. However, these programs were not performed during the whole pregnancy. Nevertheless, in most of these studies, improvements of the structures of the pelvic floor and smaller incidence of incontinences are reported.35-38 Hay-Smith et al39 found that there is some evidence that pelvic floor muscle training in women who are having their first baby can prevent urinary incontinence in late pregnancy and the postpartum period. According to Lemos et al,38 pelvic floor muscle exercises may be effective in reducing the development of postpartum urinary incontinence. It is therefore necessary to carry out a prospective study of a postpartum
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TABLE 3
Pregnancy outcome Characteristics
Exercise group (n ⴝ 34)
Control group (n ⴝ 33)
P value
Maternal
..................................................................................................................................................................................................................................... a
Weight gain during pregnancy, g
11,885 ⫾ 3146
13,903 ⫾ 2113
.03
..................................................................................................................................................................................................................................... a
Gestational age, d
277.5 ⫾ 11.5
279.5 ⫾ 11.4
⬎ .05
.....................................................................................................................................................................................................................................
⬎ .05
Type of delivery, n (%)
............................................................................................................................................................................................................................
Normal
20 (56.7)
18 (54.5)
Instrumental
7 (20.6)
5 (15.2)
Cesarean
7 (20.6)
10 (30.3)
............................................................................................................................................................................................................................ ............................................................................................................................................................................................................................ .....................................................................................................................................................................................................................................
⬎ .05
Delivery lacerations type, n (%)
............................................................................................................................................................................................................................
0
22 (64.7)
19 (57.6)
I
6 (17.6)
6 (18.2)
II
5 (14.7)
8 (24.2)
............................................................................................................................................................................................................................ ............................................................................................................................................................................................................................ ............................................................................................................................................................................................................................
III
1 (2.9)
0
..................................................................................................................................................................................................................................... a
Systolic blood pressure, mm Hg
114.4 ⫾ 9.1
113.7 ⫾ 9.6
⬎ .05
Diastolic blood pressure, mm Hg
65.9 ⫾ 7.2
66.4 ⫾ 8.4
126.04 ⫾ 29.6
123.93 ⫾ 30.1
..................................................................................................................................................................................................................................... a ..................................................................................................................................................................................................................................... a
1-h glucose level, mg/dL
..............................................................................................................................................................................................................................................
Newborn infant
..................................................................................................................................................................................................................................... a
3250 ⫾ 493
3,402 ⫾ 328
⬍4000 g, n (%)
32 (95)
30 (90)
⬎4000 g, n (%)
2 (5)
3 (10)
Birthweight, g
⬎ .05
............................................................................................................................................................................................................................ ............................................................................................................................................................................................................................
.....................................................................................................................................................................................................................................
⬎.05
Apgar score
............................................................................................................................................................................................................................ a
1-minute
8.9 ⫾ 1.1
8.8 ⫾ 1.2
5-minute
9.9 ⫾ 0.2
9.9 ⫾ 0.3
............................................................................................................................................................................................................................ ..............................................................................................................................................................................................................................................
We analyzed continuous and nominal data with t test for unpaired data at a probability level of .05. a
Data are given as mean ⫾ SD.
Barakat. Exercise during pregnancy improves maternal health perception. Am J Obstet Gynecol 2011.
group to analyze the recovery of the muscle structures of the pelvic floor that have been affected by the trauma of childbirth. Several authors believe that the perception of health status and the possible pelvic floor problems can be related to excessive maternal weight gain,40 especially in obese pregnant women.41-43 Even though many researchers have studied the relationship between physical exercise during pregnancy and maternal weight gain,26,42,44-46 only a few of them focus on the reduced possibility of alterations of the pelvic floor.38 The objective of most of the studies was to relate physical exercise during pregnancy with the maternal weight gain in combination with other pregnancy outcomes (such as,
gestational age, size and weight of the newborn infant, and type of delivery).47-49 These studies reported a reduced gain of maternal weight in the intervention groups (exercise).47-51 There are also a number of researchers who emphasize the importance of an appropriate weight control during pregnancy to avoid relevant complications (such as, gestational diabetes mellitus, hypertension, and fetal macrosomia).13,40,50 Nowadays, although an increased number of recommendations for the “practice of moderate physical activity” exists, maternal weight is controlled during pregnancy preferably through diet43,51-53 and not by means of programs of physical exercise that are controlled and supervised by obstetricians
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and sports qualified specialists. As mentioned previously, the maternal weight gain is responsible for the possible alterations of the muscles of pelvic floor. Our results have shown that the pregnant women of the EG had less maternal weight gain and similar values in the group, with a small improvement of the EG in a laceration type I. Nevertheless, even though our results are optimistic and in accordance with what is reported by other researchers,33,34,37,54 our data are not enough to conclude that a program of invigoration of the pelvic floor during gestation reduces the trauma caused by the works and the mechanisms of childbirth. More studies in pregnant women that include exercises of general muscular strengthening with those of invigoration of the pelvic floor in the same f program are necessary. REFERENCES 1. Madsen M, Jorgensen T, Jensen M, Juhl M, Olsen J, Andersen, Nybo-Andersen A. Leisure time physical exercise during pregnancy and the risk of miscarriage: a study within the Danish National Birth Cohort. BJOG 2007;114: 1419-26. 2. Van Doorn M, Lotgering F, Struijk P, Pool J, Wallenburg H. Maternal and fetal cardiovascular responses to strenuous bicycle exercise. Am J Obstet Gynecol 1992;166:854-9. 3. Artal R, Wiswell R, Drinkwater, B. Exercise in pregnancy, 2nd ed. Baltimore: Williams and Wilkins; 1991. 4. Gouveia R, Martins S, Sandes AR, et al. Pregnancy and physical exercise: myths, evidence and recommendations. Acta Med Port 2007;20:209-14. 5. Polman R, Kaiseler M, Borkoles E. Effect of a single bout of exercise on the mood of pregnant women. J Sports Med Phys Fitness 2007;47: 103-11. 6. Koltin K, Shultes S. Psychological effects of an aerobic exercise session and a rest session following pregnancy. J Sports Med Phys Fitness 1997;37:287-91. 7. Wolfe LA, Brenner IKM, Mottola MF. Maternal exercise, fetal well-being and pregnancy outcomes. Exerc Sport Sci Rev 1994;22: 145-94. 8. Hytten F, Chamberlain G. Clinical physiology in obstetrics. Blackwell Scientific Oxford, UK: Blackwell Scientific Publications; 1980. 9. Mottola M, Giroux I, Gratton R, et al. Nutrition and exercise prevents excess weight gain in overweight pregnant women. Med Sci Sports Exerc 2010;42:265-72. 10. Baeten J, Bukusi E, Lambe M. Pregnancy complications and outcomes among over-
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weight and obese nulliparous women. Am J Public Health 2001;91:436-40. 11. Langer O, Yogev Y, Xenakis E, Brustman L. Overweight and obese in gestational diabetes: the impact on pregnancy outcomes. Am J Obstet Gynecol 2005;192:1768-76. 12. Catalano P, Farrel K, Thomas A, et al. Perinatal risk factors for childhood obesity and metabolic dysregulation. Am J Clin Nutr 2009; 90:1303-13. 13. Guelinckx I, Devlieger R, Beckers K, Vansant G. Maternal obesity: pregnancy complications, gestational weight gain and nutrition. Obes Rev 2008;9:140-50. 14. Linne Y. Effects of obesity on women’s reproduction and complications during pregnancy. Obes Rev 2004;5:137-43. 15. Bowen A, Muhajarine N. Antenatal depression. Can Nurse 2006;102:26-30. 16. Poudevigne M, O’Connor P. A review of physical activity patterns in pregnant women and their relationship to psychological health. Sports Med 2006;36:19-38. 17. Poudevigne M, O’Connor P. Physical activity and mood during pregnancy. Med Sci Sports Exerc 2005;37:1374-80. 18. Barakat R, Ruiz JR, Stirling JR, Zakynthinaki M, Lucia A. Type of delivery is not affected by light resistance and toning exercise training during pregnancy: a randomized controlled trial. Am J Obstet Gynecol 2009;201:590.e1-6. 19. Barakat R, Lucia A, Ruiz JR. Resistance exercise training during pregnancy and newborn’s birth size: a randomised controlled trial. Int J Obes (Lond) 2009;33:1048-57. 20. Bungum TJ, Peaslee DL, Jackson AW, Perez MA. Exercise during pregnancy and type of delivery in nulliparae. J Obstet Gynecol Neonatal Nurs 2000;29:258-64. 21. Barakat R, Stirling J, Lucia A. Does exercise training during pregnancy affect gestational age? A randomised, controlled trial. Br J Sports Med 2008;42:674-8. 22. Slavin J, Lutter J, Cushman S, Lee V. Pregnancy and exercise. In: Pulh JL, Brown CH, Voy RO, eds. Sports perspectives for women. Champaign, IL: Human Kinetics; 1998:151. 23. Sternfeld B. Physical activity and pregnancy outcomes (rev and rec). Sport Med 1997;1: 33-47. 24. Artal R, O=Toole M. Guidelines of the American College of Obstetricians and Gynecologists for exercise during pregnancy and postpartum period. Br J Sports Med 2003;37:6-12. 25. American College of Obstetricians and Gynecologists. ACOG committee opinion no. 267: exercise during pregnancy and the postpartum period. Obstet Gynecol 2002;99:171-3. 26. Kramer MS, McDonald SW. Aerobic exercise for women during pregnancy. Cochrane Database Syst Rev 2006;19:3.
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www.AJOG.org 27. Kardel K. Effects of intense training during and after pregnancy in top-level athletes. Scand J Med Sci Sports 2005;15:79-86. 28. Ware JE, Sherbourne CD. The MOS 36item short-form health survey (SF-36). Med Care 1992;30:473-83. 29. Hueston WJ, Kasik-Miller S. Changes in functional health status during normal pregnancy. J Fam Pract 1998;47:209-12. 30. Munch S, Korst LM, Hernandez GD, Romero R, Goodwin TM. Health-related quality of life in women with nausea and vomiting of pregnancy: the importance of psychosocial context. J Perinatol 2011;31:10-20. 31. SF-36: a community for measuring health outcomes using SF tools. Available at: www.sf36.org. Accessed Oct. 14, 2010. 32. Ito H, Hagiwara M, Furuuchi T, et al. Assessments of quality of life in women with urinary incontinence using: King’s Health Questionnaire and International Consultation on Incontinence Questionnaire-Short Form. Hinyokika Kiyo 2010;56:255-9. 33. Lin Y, Tsai E, Chan T, Chou F, Lin Y. Health promoting lifestyles and related factors in pregnant women. Chang Gung Med J 2009;32: 650-61. 34. Satyapriya M, Nagendra H, Nagarathna R, Padmalatha V. Effect of integrated yoga on stress and heart variability in pregnant women. Int J Gynecol Obstet 2009;104:218-22. 35. Urizar G, Hurtz S, Ahn D, King A, Albright C, Atienza A. Influence of maternal stress on successful participation in a physical activity intervention: the IMPACT Project. Women Health 2005;42:63-82. 36. Bø K, Fleten C, Nystad W. Effect of antenatal pelvic floor muscle training on labor and birth. Obstet Gynecol 2009;113:1279-84. 37. Ismail S. The long-term effectiveness of antenatal pelvic floor muscle training: 8-year follow up of a randomised controlled trial. BJOG 2009;116:600-1. 38. Lemos A, de Souza A, Ferreira A, Figueiroa J, Cabral-Filho J. Do perineal exercises during pregnancy prevent the development of urinary incontinence? A systematic review. Int J Urol 2008;15:875-80. 39. Hay-Smith J, Mørkved S, Fairbrother KA, Herbison GP. Pelvic floor muscle training for prevention and treatment of urinary and faecal incontinence in antenatal and postnatal women. Cochrane Database Syst Rev 2008;4: CD007471. 40. Fritel X, Fauconnier A, de Tayrac R, Amblard J, Cotte L, Fernandez H. Prevent postnatal urinary incontinence by prenatal pelvic floor exercise? Rationale and protocol of the multicenter randomized study PreNatal Pelvic floor Prevention (3PN). J Gynecol Obstet Biol Reprod 2008;37:441-8.
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41. Siega-Riz AM, Evenson KR, Dole N. Pregnancy related weight gain a link to obesity? Nutr Rev 2004;62(suppl):S105-11. 42. Mottola MF. Exercise prescription for overweight and obese women: pregnancy and postpartum. Obstet Gynecol Clin North Am 2009;36:301-16. 43. Kinnunen TI, Pasanen M, Aittasalo M, et al. Preventing excessive weight gain during pregnancy: a controlled trial in primary health care. Eur J Clin Nutr 2007;61:884-91. 44. Laraia B, Messer L, Evenson K, Kaufman JS. Neighborhood factors associated with physical activity and adequacy of weight gain during pregnancy. J Urban Health 2007; 84:793-806. 45. Schlüssel M, Souza E, Reichenheim M, Kac G. Physical activity during pregnancy and maternal-child health outcomes: a systematic literature review. Cad Saude Publica 2008; 24(suppl 4):s531-44. 46. Voldner N, Frøslie K, Haakstad L, Bø K, Henriksen T. Birth complications, overweight, and physical inactivity. Acta Obstet Gynecol Scand 2009;88:550-5. 47. Domingues MR, Barros AJ, Matijasevich A. Leisure time physical activity during pregnancy and preterm birth in Brazil. Int J Gynaecol Obstet 2008;103:9-15. 48. Duncombe D, Skouteris H, Wertheim EH, Kelly L, Fraser V, Paxton SJ. Vigorous exercise and birth outcomes in a sample of recreational exercisers: a prospective study across pregnancy. Aust N Z J Obstet Gynaecol 2006; 46:288-92. 49. Dwarkanath P, Muthayya S, Vaz M, et al. The relationship between maternal physical activity during pregnancy and birth weight. Asia Pac J Clin Nutr 2007;16:704-10. 50. Clapp JF 3rd, Little KD. Effect of recreational exercise on pregnancy weight gain and subcutaneous fat deposition. Med Sci Sports Exerc 1995;27:170-7. 51. Clapp JF 3rd. Maternal carbohydrate intake and pregnancy outcomes. Proc Nutr Soc 2002;61:45-50. 52. Ørskou J, Henriksen TB, Kesmodel U, Secher NJ. Maternal characteristics and lifestyle factors and the risk of delivering high birth weight infants. Obstet Gynecol 2003;102: 115-20. 53. Olson CM. Achieving a healthy weight gain during pregnancy. Annu Rev Nutr 2008;28: 411-23. 54. De Oliveira C, Lopes MA, Carla Longo e Pereira L, Zugaib M. Effects of pelvic floor muscle training during pregnancy. Clinics 2007; 62:439-46.
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OBSTETRICS
Exercise during pregnancy improves maternal health perception: a randomized controlled trial Ruben Barakat, PhD; Mireia Pelaez, BSS; Rocio Montejo, MD, PhD; Maria Luaces, MD, PhD; Maria Zakynthinaki, PhD OBJECTIVE: We have studied the effect of moderate physical activity
that is performed by healthy women during their entire pregnancy on their perception of health status. STUDY DESIGN: Eighty sedentary women were assigned randomly to either an exercise group (n ⫽ 40) or a control group (n ⫽ 40). Maternal perception of health status and several pregnancy outcomes were recorded. RESULTS: Significant differences (P ⫽ .03) were found between study
groups in the percentage of women who perceived their health status as
“very good”; the values that corresponded to the exercise group (n ⫽ 18; 54.5%) were better than those of the control group (n ⫽ 9; 27.3%). In addition, the women of the exercise group gained less weight (11,885 ⫾ 3146 g) than those of the control group (13,903 ⫾ 2113; P ⫽ .03). CONCLUSION: A moderate physical activity program that is performed
over the first, second, and third trimester of pregnancy improves the maternal perception of health status. Key words: exercise, pregnancy, maternal health, weight gain
Cite this article as: Barakat R, Pelaez M, Montejo R, et al. Exercise during pregnancy improves maternal health perception: a randomized controlled trial. Am J Obstet Gynecol 2011;204:402.e1-7.
P
hysical exercise has gained increasing popularity among women of fertile age; many women ask for medical advice on whether they can continue to exercise throughout their pregnancy.1 The greater the number of pregnant women who want to participate in sports activities, the more important becomes the question about influence of exercise on mother and fetus.2 Historically, women have received various advice regarding a better pregnancy and labor. These were recommendations from different groups of profesFrom the Facultad de Ciencias de la Actividad Física y del Deporte – INEF, Universidad Politécnica de Madrid (Drs Barakat and Zakynthinaki, and Ms Pelaez); and the Hospital de Fuenlabrada (Drs Montejo and Luaces), Madrid, Spain. Received Aug. 17, 2010; revised Dec. 21, 2010; accepted Jan. 18, 2011. Reprints: Maria Zakynthinaki, PhD, Instituto de Ciencias Matemáticas, CSIC - UAM - UC3M UCM, c/ Serrano 121, 28006 Madrid, Spain. [email protected]. Authorship and contribution to the article is limited to the 5 authors indicated. There was no outside funding or technical assistance with the production of this article. 0002-9378/$36.00 © 2011 Mosby, Inc. All rights reserved. doi: 10.1016/j.ajog.2011.01.043
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sionals, religious leaders, philosophers, and doctors.3 However, when the physical and physiologic mechanisms and processes of pregnancy started to be understood, the advice to women regarding the type of the appropriate physical exercise during pregnancy became more precise.4 Despite the scientific findings, some questions still exist among the researchers regarding the influence of physical exercise on several aspects of pregnant women (ie, psychologic factors). A few studies have focused on the psychologic benefits on exercise during pregnancy.5,6 Pregnancy is a unique human process in which all the body control systems are modified to maintain maternal and fetal homeostasis.7 One of the most important changes during pregnancy is the metabolism of the mother, which results in a normal weight gain during pregnancy of approximately 9-11 kg.8 Any additional increase in the maternal weight is an energy reserve so that the mother can later feed her baby, but it also is a risk for maternal overweight, obesity, and complications to maternal health status.9 Obese women have increased possibilities of the development of future pelvic floor problems. This fact, combined with the increased frequency of complications during labor that are caused by
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obesity,10-12 puts these women in a group at special risk of poor quality of life.13 It should be noted here that pelvic floor problems (urinary and fecal incontinence, hyperactive bladder, pain during sexual relations, and pelvic prolapse) still remain a taboo subject. In many cases, these problems are thought erroneously to be the inherent consequence of having gone through labor. The reason for this is more cultural than scientific and seriously affects maternal perception of health status.14 Regular participation in exercise programs has been associated with primary and secondary prevention of numerous physical health problems.5 There is also strong evidence that moderate exercise results in a more positive self-concept, improved mental well-being, an enhanced sense of well-being, a higher quality of life, and an improved mood.15-17 When a pregnant woman exercises, her improved muscular strength may be beneficial especially in preventing back pain, may help in feeling agile and nimble, and may facilitate the added weight and the changing center of gravity.3 Also, recent studies in this area have shown that physical exercise during pregnancy plays an important role in the prevention of obesity and excessive weight gain and in control of the weight of women who
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www.AJOG.org are already obese; this can be achieved without any maternal-fetal risks, as far as pregnancy outcomes are concerned.18-21 The traditional recommendations regarding physical activity during pregnancy have been based more on cultural and social matters rather than scientific evidence.22,23 Even nowadays, doubts exist among both obstetricians and sport scientists regarding the type, the intensity, the duration, and the frequency of physical exercise during pregnancy and its influence on the maternal psychologic aspects. A more important aspect is the maternal perception of health status. Adequate research in this area of science is therefore necessary. This becomes even more obvious when one takes into account the fact that everyday more women want to continue to exercise in some form, during their pregnancy.22 The aim of this study was to investigate the influence of a program of moderate physical exercise during the entire pregnancy on maternal perception of health status and other pregnancy outcomes.
M ATERIALS AND M ETHODS The present study was a randomized, controlled training trial. We contacted a total of 360 Spanish (white) women in a low-to-medium socioeconomic class (the contact was made by the obstetrician during the first prenatal visit). From the initial number of pregnant women, finally 67 women were studied (Figure). The research protocol was reviewed and approved by our Ethics Committee and followed the ethical guidelines of the Declaration of Helsinki, which was last modified in 2008. The research was carried out in collaboration with the Obstetric Hospital Department (Hospital de Fuenlabrada, Madrid, Spain). All participants were informed about the aim and study protocol, and written informed consent was provided by all women. All exercises were carried out under the supervision of an obstetrician.
Subjects We randomly assigned (by use of a random number table) 80 healthy pregnant
women (age, 23-38 years) to either an exercise group (EG; n ⫽ 40) or a control group (CG; n ⫽ 40). Women not planning to give birth in the same obstetrics hospital department (Hospital de Fuenlabrada, Madrid, Spain) and not receiving medical follow-up evaluations throughout the entire pregnancy period were not included in the study. Both groups included subjects with similar prepregnancy level of physical activity or type of recreational exercise. All the women were healthy and had uncomplicated and singleton pregnancies. The exclusion criteria were any type of absolute obstetric contraindication to aerobic exercise during pregnancy,24,25 which included other contraindications that the authors considered to have a relevant influence on maternal perception of health: hemodynamically significant heart disease, restrictive lung disease, incompetent cervix/cerclage, multiple gestation, risk of premature labor, preeclampsia/pregnancy induced hypertension, thrombophlebitis, recent pulmonary embolism (last 5 years), acquired infectious disease, retarded interuterine development, serious blood disease, and/or absence of prenatal control.
Exercise program The physical conditioning program included a total of 35- to 45-minute weekly sessions 3 days each week (Monday, Wednesday, Friday) from the start of the pregnancy (weeks 6-9) to the end of the third trimester (weeks 38-39). Thus, an average of 85 training sessions was planned originally for each participant in the event of no preterm delivery. All subjects used a heart rate monitor (Accurex Plus; Polar Electro OY, Oulu, Finland) during the training sessions to ensure that exercise intensity was light-to-moderate (that is, their heart rate was consistently under 70% of their age-predicted maximum heart rate value [220 minus age]). Each session included a 25-minute core session that was preceded and followed by a gradual warm-up and cooldown period, respectively (both of 7-8 minute duration and consisting of walking and light, static stretching [avoiding muscle pain] of most muscle groups [upper and lower limbs, neck and trunk
Research
muscles]). The cool-down period also included relaxation and pelvic floor exercises. The core session included the following toning and very light resistance exercises: toning and joint mobilization exercises that included shoulder shrugs and rotations, arm elevations, leg lateral elevations, pelvic tilts, and rocks. Resistance exercises were performed through the full range of motion that normally is associated with correct technique for each exercise and engaged the major muscle groups (pectoral, dorsal, shoulder, upper and lower limb muscles). They included 1 set (10-12 repetitions of each) of abdominal curls and the following exercises with barbells (3 kg/exercise) or low-to-medium resistance bands (Therabands; The Hygenic Corporation, Akron, OH): biceps curls, arm extensions, arm side lifts, shoulder elevations, bench press, seated lateral row, lateral leg elevations, leg circles, knee extensions, knee (hamstring) curls, ankle flexion, and extensions. We specifically avoided any exercises that involved extreme stretching and joint overextension, ballistic movements or jumps. Any type of exercises on the back were performed for no more than 2 minutes.3,26 We used exercises that covered the major muscle groups of arms and abdomen to promote good posture and prevent low back pain and, in the third trimester, to strengthen the muscles of labor and pelvic floor.27 We also included in the program 1 session per week of aerobic dance. To maximize safety, adherence to the training program, and its efficacy, all sessions were supervised by a qualified fitness specialist (working with groups of 10 –12 subjects) and with the assistance of an obstetrician, were accompanied by music, and were performed in the hospital, in a spacious, well-lit room under favorable environmental conditions (altitude 600 m; temperature, 19-21°C; humidity, 50 – 60%). The following general considerations were given to the exercise program: All the activity was of aerobic type, and an adequate intake of calories and nutrients was assured before the start of the exercise program. As a general rule and to avoid potential risks, the following
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FIGURE
CONSORT 2010 flow diagram of the study participants
CONSORT, Consolidated Standards of Reporting Trials. Barakat. Exercise during pregnancy improves maternal health perception. Am J Obstet Gynecol 2011.
activities were avoided: activities that included Valsalva’s mechanism; high room temperatures or humid environments, with the aim to avoid chances of hyperthermia (body temperature, ⬎38°C); ballistics movements; and positions of extreme muscular tension. 402.e3
Variables of the study The following maternal characteristics have been taken into account: age, body mass index, smoking habits, alcohol intake, occupational activity, time standing per day, time of domestic task, educational level, and parity.
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The variables that are related to health perception and urinary incontinences were perception of health status level and frequency to pregnant women lose urine. The SF-36 King’s Health Questionnaire has been used.28-31 This test is a
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TABLE 1
Maternal characteristics Maternal characteristics Maternal age, y
a
Exercise group (n ⴝ 34)
Control group (n ⴝ 33)
P value
31 ⫾ 3
30 ⫾ 3
⬎ .05
23.9 ⫾ 3
24.8 ⫾ 4
.............................................................................................................................................................................................................................................. 2
Body mass index, kg/m
..............................................................................................................................................................................................................................................
⬎ .05
Smoking habits, n (%)
.....................................................................................................................................................................................................................................
Yes
3 (8.8)
6 (18.2)
No
23 (67.7)
22 (66.7)
8 (23.5)
5 (15.1)
..................................................................................................................................................................................................................................... .....................................................................................................................................................................................................................................
Before pregnancy, not now
..............................................................................................................................................................................................................................................
⬎ .05
Alcohol intake, n (%)
.....................................................................................................................................................................................................................................
Yes
1 (4)
3 (7)
No
33 (96)
30 (93)
..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
⬎ .05
Occupational activity, n (%)
.....................................................................................................................................................................................................................................
Sedentary job
14 (41.2)
14 (42.4)
Housewife
3 (8.8)
5 (15.2)
Active job
17 (50.0)
14 (42.4)
..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
⬎ .05
Standing, n (%)
.....................................................................................................................................................................................................................................
⬎3 h
19 (55.9)
13 (34.9)
⬍3 h
15 (44.1)
20 (60.6)
..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
⬎ .05
Domestic tasks, n (%)
.....................................................................................................................................................................................................................................
⬎2 h
12 (35.3)
16 (48.5)
⬍2 h
22 (64.7)
17 (51.5)
..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
⬎ .05
Education, n (%)
.....................................................................................................................................................................................................................................
⬍High school
3 (8.8)
6 (18.2)
High school
16 (47.1)
19 (57.6)
⬎High school
15 (44.1)
8 (24.2)
..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
Parity
.04
.....................................................................................................................................................................................................................................
0
26 (76.5)
12 (36.4)
1
8 (23.5)
20 (60.6)
⬎1
0
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The pregnancy outcomes that were considered were maternal weight gain, gestational age, type of delivery, delivery lacerations, blood pressure, 1-hour glucose tolerance, birthweight, and Apgar score.
Data analysis Our data were analyzed with the use of the Student t test for independent samples (Tables 1-3). A power analysis was conducted to determine the number of participants needed to reach a 2 value with an adequate level of statistical power. This analysis confirmed that adequate power (⬎ .80) with an 95% confidence level and a confidence interval of 10% (we allowed for 10% dropouts over 20 weeks) would be achieved with 40 pregnant women in the EG and with 40 pregnant women in the CG. We provide maternal characteristics of the study sample by groups (EG and CG) in terms of means and SDs, unless otherwise stated. For group comparisons of pregnancy outcomes, we analyzed continuous and nominal data with t test for unpaired data. We compared Apgar scores between groups using the nonparametric Mann-Whitney U test. Statistical analysis was performed with the Statistical Package for Social Sciences software (version 14.0 for Windows; SPSS Inc, Chicago, IL); the level of significance was set to ⬍ .05.
..................................................................................................................................................................................................................................... .....................................................................................................................................................................................................................................
1 (3.0)
.............................................................................................................................................................................................................................................. a
Data are expressed as mean ⫾ SD.
Barakat. Exercise during pregnancy improves maternal health perception. Am J Obstet Gynecol 2011.
multipurpose, short-form health survey with only 36 questions and yields an 8-scale profile of functional health and well-being scores, psychometrically based physical and mental health summary measures, and a preference-based health utility index. The CIQ-SF Incontinence classification of the International Continence Society has also been used.32 This test measures the subjective grade of urinary incontinence (regarding the patient) and its impact on quality of life.
Because the aim of the study was to observe the influence of exercise on the process of pregnancy and delivery, the questionnaires were given to the subjects after delivery. The study assumed that all participating subjects had started their pregnancy with the same (good) level of perception of their health status, which was confirmed during their first prenatal visit. Regarding incontinence problems, women who experienced such problems before pregnancy were excluded from the study.
R ESULTS Our results are presented in Table 1 (maternal characteristics), Table 2 (maternal perception of state of health and frequency of pregnant women to lose urine), and Table 3 (pregnancy outcomes). According to our analysis and regarding adherence to training and its possible adverse effects, we report that 6 women from the EG discontinued the intervention because of diagnosed risk for premature labor (n ⫽ 1), pregnancy-induced hypertension (n ⫽ 1), and personal reasons (n ⫽ 4). Seven participants of the CG were excluded from the study because of pregnancy-induced hypertension (n ⫽ 2), threat of premature delivery (n ⫽ 2), and personal reasons (n ⫽ 3). The final number of participants
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were 34 pregnant women in the EG and 33 pregnant women in the CG. There were no exercise-related injuries experienced during pregnancy. Adherence to training in the experimental group was 90%. No women changed from the CG to the EG or vice versa, and there were no protocol deviations from the study as planned. At the beginning of our study, we found no between-group differences regarding the potential confounding variables (such as occupational activities, standing, smoking habits, alcohol intake). Parity was the only exception; the EG presented a major percentage of nulliparaous women (76.5%) than did the CG (36.4%; P ⫽ .04). Regarding the perception that a pregnant woman has about her health status and the problems that are associated with her pelvic floor (incontinences), the women who performed a program of physical exercise reported a better health status than those who did not participate in any program (Table 2). In fact, although 18 women (54.5%) of the EG perceived that their health status was “very good,” the respective number of women in the CG was only 9 (27.3%; P ⫽ .03). Concerning incontinence perception of our study subjects, no significant differences between the study groups have been found, although the most prominent factor is surely the question of how frequently a pregnant woman has urine loss; in the CG, there were 3 women (9.1%) who reported “several times by day”; in the EG, there was only 1 woman (2.9%). As we show in Table 3, the pregnant women of the EG gained less weight (11,885 ⫾ 3146 g) than did the women in the CG (13,903 ⫾ 2113 g; P ⫽ .03). It should be noted that, according to our results, the weight gain of the pregnant women in the EG is considered normal for a healthy pregnancy. We found values moderately encouraging in the section of lacerations that were produced by the mechanics of the childbirth (Table 2); in laceration of type I, 8 women (24.2%) of the CG were reported vs 5 women of the EG (14.7%). 402.e5
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TABLE 2
Maternal perception of state of health and frequency of pregnant women to lose urine Variable
Exercise group (n ⴝ 34)
Control group (n ⴝ 33)
Maternal perception of health status, n (%)
P value .03
.....................................................................................................................................................................................................................................
Very bad
1 (3.0)
1 (3.0)
Some bad
0
5 (15.2)
..................................................................................................................................................................................................................................... .....................................................................................................................................................................................................................................
Good
14 (42.4)
18 (54.5)
Very good
18 (54.5)
9 (27.3)
..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
⬍ .05
Frequency of pregnant women to lose urine, n (%)
.....................................................................................................................................................................................................................................
Never
24 (70.6)
22 (66.7)
Once a week
5 (14.7)
5 (15.2)
2-3 times/week
2 (5.9)
1 (3.0)
Once a day
2 (5.9)
2 (6.1)
Several times a day
1 (2.9)
3 (9.1)
Continually
0
0
..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..................................................................................................................................................................................................................................... ..............................................................................................................................................................................................................................................
Barakat. Exercise during pregnancy improves maternal health perception. Am J Obstet Gynecol 2011.
C OMMENT The aim of the present work was to study the possible effects of aerobic exercise during pregnancy on the perception of maternal health status, weight gain during pregnancy, and urinary incontinence. Our results showed an increased perception of health status in the EG (P ⫽ .03). This is in accordance with authors who reported physical activity as a factor to improve the perception of maternal health or health-promoting lifestyles.33 A number of authors reported that the physical exercise acts as an important factor to improve psychologic factors; most of these studies concern mood or stress level of a pregnant woman.34,35 Pregnancy is a period of important changes in all the body control systems that result in modifications in a woman’s psychologic status and the relevant emotional instability.3 The present study shows that a physical activity program could minimize these modifications and emotional complications and thus contribute to a healthy pregnancy. There is sufficient evidence that demonstrates that exercise during pregnancy (and during every other period of life) is beneficial not only regarding the physio-
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logic aspects but also regarding a woman’s perception of well-being.5,6 We believe that a program of moderate physical exercise during pregnancy not only can improve the maternal perception of health status but also can contribute to the strengthening of other emotional factors during pregnancy and after delivery. Specifically as related to the incontinences and the complications of pelvic floor, some researchers have presented programs of physical exercise that are dedicated only to the invigoration of the pelvic floor muscles. However, these programs were not performed during the whole pregnancy. Nevertheless, in most of these studies, improvements of the structures of the pelvic floor and smaller incidence of incontinences are reported.35-38 Hay-Smith et al39 found that there is some evidence that pelvic floor muscle training in women who are having their first baby can prevent urinary incontinence in late pregnancy and the postpartum period. According to Lemos et al,38 pelvic floor muscle exercises may be effective in reducing the development of postpartum urinary incontinence. It is therefore necessary to carry out a prospective study of a postpartum
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TABLE 3
Pregnancy outcome Characteristics
Exercise group (n ⴝ 34)
Control group (n ⴝ 33)
P value
Maternal
..................................................................................................................................................................................................................................... a
Weight gain during pregnancy, g
11,885 ⫾ 3146
13,903 ⫾ 2113
.03
..................................................................................................................................................................................................................................... a
Gestational age, d
277.5 ⫾ 11.5
279.5 ⫾ 11.4
⬎ .05
.....................................................................................................................................................................................................................................
⬎ .05
Type of delivery, n (%)
............................................................................................................................................................................................................................
Normal
20 (56.7)
18 (54.5)
Instrumental
7 (20.6)
5 (15.2)
Cesarean
7 (20.6)
10 (30.3)
............................................................................................................................................................................................................................ ............................................................................................................................................................................................................................ .....................................................................................................................................................................................................................................
⬎ .05
Delivery lacerations type, n (%)
............................................................................................................................................................................................................................
0
22 (64.7)
19 (57.6)
I
6 (17.6)
6 (18.2)
II
5 (14.7)
8 (24.2)
............................................................................................................................................................................................................................ ............................................................................................................................................................................................................................ ............................................................................................................................................................................................................................
III
1 (2.9)
0
..................................................................................................................................................................................................................................... a
Systolic blood pressure, mm Hg
114.4 ⫾ 9.1
113.7 ⫾ 9.6
⬎ .05
Diastolic blood pressure, mm Hg
65.9 ⫾ 7.2
66.4 ⫾ 8.4
126.04 ⫾ 29.6
123.93 ⫾ 30.1
..................................................................................................................................................................................................................................... a ..................................................................................................................................................................................................................................... a
1-h glucose level, mg/dL
..............................................................................................................................................................................................................................................
Newborn infant
..................................................................................................................................................................................................................................... a
3250 ⫾ 493
3,402 ⫾ 328
⬍4000 g, n (%)
32 (95)
30 (90)
⬎4000 g, n (%)
2 (5)
3 (10)
Birthweight, g
⬎ .05
............................................................................................................................................................................................................................ ............................................................................................................................................................................................................................
.....................................................................................................................................................................................................................................
⬎.05
Apgar score
............................................................................................................................................................................................................................ a
1-minute
8.9 ⫾ 1.1
8.8 ⫾ 1.2
5-minute
9.9 ⫾ 0.2
9.9 ⫾ 0.3
............................................................................................................................................................................................................................ ..............................................................................................................................................................................................................................................
We analyzed continuous and nominal data with t test for unpaired data at a probability level of .05. a
Data are given as mean ⫾ SD.
Barakat. Exercise during pregnancy improves maternal health perception. Am J Obstet Gynecol 2011.
group to analyze the recovery of the muscle structures of the pelvic floor that have been affected by the trauma of childbirth. Several authors believe that the perception of health status and the possible pelvic floor problems can be related to excessive maternal weight gain,40 especially in obese pregnant women.41-43 Even though many researchers have studied the relationship between physical exercise during pregnancy and maternal weight gain,26,42,44-46 only a few of them focus on the reduced possibility of alterations of the pelvic floor.38 The objective of most of the studies was to relate physical exercise during pregnancy with the maternal weight gain in combination with other pregnancy outcomes (such as,
gestational age, size and weight of the newborn infant, and type of delivery).47-49 These studies reported a reduced gain of maternal weight in the intervention groups (exercise).47-51 There are also a number of researchers who emphasize the importance of an appropriate weight control during pregnancy to avoid relevant complications (such as, gestational diabetes mellitus, hypertension, and fetal macrosomia).13,40,50 Nowadays, although an increased number of recommendations for the “practice of moderate physical activity” exists, maternal weight is controlled during pregnancy preferably through diet43,51-53 and not by means of programs of physical exercise that are controlled and supervised by obstetricians
Research
and sports qualified specialists. As mentioned previously, the maternal weight gain is responsible for the possible alterations of the muscles of pelvic floor. Our results have shown that the pregnant women of the EG had less maternal weight gain and similar values in the group, with a small improvement of the EG in a laceration type I. Nevertheless, even though our results are optimistic and in accordance with what is reported by other researchers,33,34,37,54 our data are not enough to conclude that a program of invigoration of the pelvic floor during gestation reduces the trauma caused by the works and the mechanisms of childbirth. More studies in pregnant women that include exercises of general muscular strengthening with those of invigoration of the pelvic floor in the same f program are necessary. REFERENCES 1. Madsen M, Jorgensen T, Jensen M, Juhl M, Olsen J, Andersen, Nybo-Andersen A. Leisure time physical exercise during pregnancy and the risk of miscarriage: a study within the Danish National Birth Cohort. BJOG 2007;114: 1419-26. 2. Van Doorn M, Lotgering F, Struijk P, Pool J, Wallenburg H. Maternal and fetal cardiovascular responses to strenuous bicycle exercise. Am J Obstet Gynecol 1992;166:854-9. 3. Artal R, Wiswell R, Drinkwater, B. Exercise in pregnancy, 2nd ed. Baltimore: Williams and Wilkins; 1991. 4. Gouveia R, Martins S, Sandes AR, et al. Pregnancy and physical exercise: myths, evidence and recommendations. Acta Med Port 2007;20:209-14. 5. Polman R, Kaiseler M, Borkoles E. Effect of a single bout of exercise on the mood of pregnant women. J Sports Med Phys Fitness 2007;47: 103-11. 6. Koltin K, Shultes S. Psychological effects of an aerobic exercise session and a rest session following pregnancy. J Sports Med Phys Fitness 1997;37:287-91. 7. Wolfe LA, Brenner IKM, Mottola MF. Maternal exercise, fetal well-being and pregnancy outcomes. Exerc Sport Sci Rev 1994;22: 145-94. 8. Hytten F, Chamberlain G. Clinical physiology in obstetrics. Blackwell Scientific Oxford, UK: Blackwell Scientific Publications; 1980. 9. Mottola M, Giroux I, Gratton R, et al. Nutrition and exercise prevents excess weight gain in overweight pregnant women. Med Sci Sports Exerc 2010;42:265-72. 10. Baeten J, Bukusi E, Lambe M. Pregnancy complications and outcomes among over-
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