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Sleep quality at 3 months postpartum considering maternal age: A comparative study
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Women and Birth xxx (2018) xxx–xxx
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Women and Birth journal homepage: www.elsevier.com/locate/wombi
Original Research - Quantitative
Sleep quality at 3 months postpartum considering maternal age: A comparative study Shih-Yi Wena , Yi-Li Kob , Hei-Jen Jouc , Li-Yin Chiend,* a
Department of Obstetrics and Gynecology, Fu Jen Catholic University Hospital, New Taipei City, Taiwan Department of Nursing, Fu Jen Catholic University, New Taipei City 24205, Taiwan c Department of Obstetrics and Gynecology, Taiwan Adventist Hospital, Taipei, Taiwan d Institute of Community Health Care, National Yang-Ming University, Taipei, Taiwan b
A R T I C L E I N F O
A B S T R A C T
Article history: Received 2 October 2017 Received in revised form 5 February 2018 Accepted 9 February 2018 Available online xxx
Background: Poor sleep quality is related to old age among the general population, but few studies have focused on postpartum women of advanced maternal age. The present study aimed to describe and compare sleep quality between women younger or older than 35 years of age at 3 months postpartum, and to examine the related factors. Methods: A cross-sectional survey was conducted with 160 postpartum women who had given birth at a teaching hospital in Taiwan. The participants were assigned to two groups according to age (35 years, n = 80; and 20–34 years, n = 80). Sleep quality was measured using the Pittsburgh Sleep Quality Index with a cut-off score of 5. Results: The prevalence of poor sleep quality at 3 months postpartum was higher in older mothers (61.6%) than in younger mothers (38.4%, p < 0.01). Multiple logistic regression revealed that poor sleep quality was positively correlated with the severity of postpartum physical symptoms, lack of exercise, and roomsharing with infants. After adjustment for those variables, older mothers were three times more likely to have poor sleep quality than younger mothers (odds ratio = 3.08; 95% confidence interval 1.52–6.23). Conclusion: Health care providers should pay attention to sleep problems among postpartum women, especially mothers of advanced maternal age. In particular, health care providers should evaluate sleep quality among postpartum women, instruct them not to share the bed with their infants at night, perform exercise, and manage their postpartum physical symptoms to improve the sleep quality. © 2018 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.
Keywords: Sleep Postpartum period Sleep quality Maternal age Maternal health
Statement of significance
Problem Advanced maternal age has become more common in modern society, however, its’ association with postpartum sleep quality remained unclear.
What this paper adds Mothers 35 years of age were three times more likely to have poor sleep quality than younger mothers after adjustment for the three factors that were significantly positively associated with poor sleep quality; severity of postpartum physical symptoms, lack of exercise, and roomsharing with infants.
What is already known Poor sleep quality is common among postpartum women. Factors related to poor sleep quality included sociodemographics, obstetrical history, infant care, personal health history and symptoms, and lifestyle factors.
* Corresponding author at: 155 Li-Nong Street, Sec. 2, Bei-Tou, Taipei 11221, Taiwan. E-mail address: [email protected] (L.-Y. Chien).
1. Introduction Advanced maternal age has recently become more common in Taiwan. Between 2006 and 2016, the proportion of primiparous women aged 35 years or older increased from 33.05% to 36.73%,1 and the mean maternal age at birth increased from 30.9 years in 20132 to 31.9 years in 2016.1 Childbearing at an advanced maternal age is a growing clinical concern because women with advanced maternal age have generally high-risk pregnancies and births.3–5
https://doi.org/10.1016/j.wombi.2018.02.004 1871-5192/© 2018 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.
Please cite this article in press as: S.-Y. Wen, et al., Sleep quality at 3 months postpartum considering maternal age: A comparative study, Women Birth (2018), https://doi.org/10.1016/j.wombi.2018.02.004
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Indeed, advanced maternal age was associated with an increased risk of pregnancy complications, caesarean births, preterm births, and postpartum physical symptoms.3–5 In addition, older mothers may demonstrate several physical and psychosocial characteristics or limitations, such as poor physical strength6 and limited social support.7 Those factors may interfere with maternal adaptation after childbirth. Advanced maternal age has also been associated with postpartum depression, particularly in primiparous women.8 In the postpartum period, infants typically require frequent feedings at night that result in frequent waking after sleep onset, reduced sleep duration, and reduced time of asleep in night among mothers.9 Sleep disturbance is an important health issue in postpartum women, because of its association with fatigue, depression, and emotional disturbance.10–12 Previous studies on subjective sleep quality in postpartum women using Pittsburgh Sleep Postnatal Depression Scale (PSQI)13–15 indicated that the sleep quality is disrupted immediately after childbirth, followed by an improvement; however, it remains a problem during the first 2–3 months postpartum for many women. In addition, the sleep quality has been reported to decline with age in adults.16 However, most previous studies have focused on sleep quality among young postpartum women, and only few studies reported on postpartum sleep quality in mothers with advanced maternal age. The objectives of the present study were to describe and compare sleep quality between women 20–34 years or 35 years of age at 3 months postpartum, and to examine the related factors in Taipei City, Taiwan. 2. Participants, ethics, and methods 2.1. Sample size estimation Based on results of a previous study,17 we hypothesised that the effect size of differences in sleep quality between women with and without advanced maternal age was 0.5. Using G power 3.1.7, the required sample size was 64 per group when effect size was 0.5, two-sided a was 0.05, and power was 0.8. To account for rejection and missing data, we decided to recruit 80 women each for women with and without advanced maternal age. 2.2. Design and participants In this cross-sectional survey, we recruited women who hospitalized at a postpartum ward of a regional teaching hospital in Taipei, Taiwan. The inclusion criteria were adult women (20 years of age) without severe maternal or neonatal complications and who can communicate in Mandarin Chinese or Taiwanese. During the period between February 2014 and December 2014, the first author assessed eligibility of the study participants at the ward every 3 days. She approached women who were eligible to be enrolled in the study and explained the study purpose to ask whether the women agreed to participate and to be telephoneinterviewed about 3 months later. The recruitment was conducted in a consecutive of presentations to the hospital until the desired sample size and proportion of parity was reached. In accordance with the requirement of the institutional review board at the study hospital, those women who agreed to participate signed a consent form and left their contact phone number to the first author. Of the 183 women approached, 23 refused to participate in the study. In total, 160 postpartum women were enrolled, of whom 80 were aged 35 years or older (advanced age group) and 80 were aged 20– 34 years (non-advanced age group). The two groups were frequency-matched for parity. Since half of the women in the advanced age group were primiparous (n = 40) and the remaining were multiparous (n = 40), we recruited the same proportion of parity in the non-advanced age group. The study participants were
interviewed by the first author using structured questionnaires at 12–14 weeks postpartum during 15 to 20-min telephone interviews from May 2014 through February 2015. This study was approved by the institutional review board at the Taiwan Adventist Hospital (No. 103-E-01). 2.3. Measurements Based on literature review and clinical observations, we designed the study tool. The study tools included the following: (1) a self-designed structured questionnaire, which comprised basic information and pregnancy/childbirth history, healthy life style, and newborn care variables; (2) the Postpartum Physical Symptoms Checklist (PPSC); and (3) the Pittsburgh Sleep Quality Index (PSQI). The basic information included age, work status, education level, and family socio-economic status. The family socioeconomic status was determined based on the Hollingshead 2factor index of social position. The highest level of education and occupation of each couple were used to calculate the index based on the following equation: (education level 4) + (occupational level 7). The index was divided into high (41–55), middle (30– 40), and low (11–29) groups.18 The obstetrical history included parity, birth mode, preterm birth, and infant sex. The personal lifestyle included the behaviour of coffee/tea drinking and exercise in the past 2 weeks. The newborn care variables included the infant feeding method and sleeping arrangements for the baby. Content validity of the self-designed structured questionnaire was reviewed by 5 experts, including 2 obstetricians, 1 clinical nursing instructor, 1 nursing professor, and 1 deputy head nurse of postpartum ward. The experts rated the appropriateness of the questions on a 5-point Likert-scale (from 1 to 5) and provided feedback on revising the question if a question received a score of <3. The content validity index was 0.98, i.e., 98% of the questions received a score of 3. The PPSC was designed to measure the severity of postpartum physical symptoms among postpartum women.3 The original checklist contained 18 common postpartum physical symptoms, including caesarean section wound or perineal pain, constipation, backache, headache, haemorrhoids, joint pain, numbness in the hands, excessive leucorrhoea, vaginal infection, numbness in the feet, urinary-tract infection, excessive vaginal bleeding, dizziness, varicose vein over legs, urinary incontinence, a higher incidence of cold than usual, and cold hands and/or feet. The content validity of the PPSC had been established through experts review. The internal consistency of the scale as assessed by Cronbach's a among women at one month postpartum in Taiwan was 0.77.3 We deleted one item in this study, namely the poor sleep quality, because it overlapped with the dependent variable. A 4-point Likert-scale ranging from 0 to 3 (none, mild, moderate, severe) was applied to each item in the PPSC, for a total scale range of 0–51 points, with higher scores suggesting severer physical symptoms. The internal consistency of the scale as assessed by Cronbach's a was 0.56 for the 18 items and 0.54 for the 17 items (deleting poor sleep quality) in this study. Sleep quality was measured using the PSQI,19 which consisted of seven sleep components: subjective sleep quality, sleep latency, sleep duration, sleep efficiency, sleep disturbance, day-time dysfunction, and use of sleeping medication. Items were measured using a 4-point Likert-scale ranging from 0 to 3. The sum of the seven component scores formed a global PSQI score (range 0–21), with higher scores indicating a poorer quality of sleep. A cut-off score of 5 was used to demarcate good sleepers from poor sleepers. The PSQI was previously shown to be a reliable and valid tool in measuring quality of sleep.19 The PSQI was translated into Chinese
Please cite this article in press as: S.-Y. Wen, et al., Sleep quality at 3 months postpartum considering maternal age: A comparative study, Women Birth (2018), https://doi.org/10.1016/j.wombi.2018.02.004
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and back-translated into English by bilingual people with bicultural experience to establish content and semantic equivalence.20 The PSQI has been used to measure sleep quality among perinatal and postpartum women in many previous studies.13–15 Internal consistency (Cronbach's a) for the Chinese PSQI was assessed at 0.73 in this study. 2.4. Data analysis Descriptive analyses were performed by calculating frequencies, percentages, means, and standard deviations (SD). Pearson's chi-squared tests or Fisher's exact tests were used to examine differences in characteristics between women of the two age groups. Fisher's exact tests were used when at least one cell of the table had an expected count smaller than 5. Multiple logistic regression analysis was used to identify factors related to poor sleep quality and to examine the net effect of advanced maternal age on poor sleep quality given that other variables in the model were adjusted for. We started with a model for poor sleep quality with only advanced age as the independent variable. Then, in forward stepwise selections, we added independent variables that were significantly related to breastfeeding. The final logistic regression model included all significant variables (two-sided pvalue < 0.05) and estimated adjusted odds ratios of the included variables. Data analysis was performed using the Statistical
3
Package for the Social Sciences (SPSS) for Windows version 18.0 (SPSS Inc, Chicago, Illinois). 3. Results Of the 160 participants recruited, 80 were aged 35 years or more (advanced maternal age; mean age, 37.2 1.8 years; range 23.6–34.9 years) and 80 were younger than 35 years of age (nonadvanced maternal age; mean age, 31.7 2.7 years; range 35.1– 44.3 years). Characteristics between participants with advanced and non-advanced maternal age were compared in Table 1. Half of the participants in each age group were primipara. The mothers were predominantly college or university educated (68%), and the majority was employed (67%). Most birth modes were vaginal (76%) and most mothers practiced mixed formula feeding and breastfeeding (82%). Mothers of the advanced age group had higher social economic status (60%) than those of the non-advanced age group (41.3%; p = 0.030). The rate of preterm birth was higher (8.8%) in the advanced age group than in the non-advanced age group (0%; p = 0.01). Approximately 48.8% of the mothers were room-sharing, but not bed-sharing, with their infants, 42.5% were bed-sharing with their infants, and only 8.8% did not share the room or bed with their infants. Approximately 70% of the mothers drank tea or coffee, while only 31% of mothers reported exercise in the past 2 weeks. There were
Table 1 Characteristics of the study participants (n = 160). Characteristics
Work status No Yes Education level High school or below Vocational school University or collage Graduate school Family socio-economic status Middle or low High Parity 1 2 3 Birth mode Vaginal Caesarean Preterm birth No Yes Infant sex Male Female Sleeping arrangements for infants Sharing room, not bed Sharing bed None Infant feeding Exclusive breastfeeding Mixed feeding Formula Coffee/tea drinking (past 2 weeks) Yes No Exercise (past 2 weeks) Yes No a *
Non-advanced age n (%) n = 80
Advanced age n (%) n = 80
29 (36.3) 51 (63.8)
24 (30.0) 56 (70.0)
6 (7.5) 8 (10) 52 (65.0) 14 (17.4)
4 (5.0) 11 (13.8) 38 (47.5) 27 (33.8)
47 (58.8) 33 (41.3)
32 (40.0) 48 (60.0)
40 (50.0) 34 (42.5) 6 (7.5)
40 (50.0) 30 (37.5) 10 (12.5)
66 (82.5) 14 (17.5)
56 (70.0) 24 (30.0)
80 (100) 0 (0)
73 (91.3) 7 (8.8)
30 (37.5) 50 (62.5)
42 (52.5) 38 (47.5)
42 (53.8) 33 (41.2) 5 (6.2)
36 (46.2) 35 (43.8) 9 (11.3)
41 (51.3) 25 (31.3) 14 (17.5)
31 (38.8) 34 (42.5) 15 (18.8)
55 (68.8) 25 (31.3)
58 (72.5) 22 (27.5)
25 (31.3) 55 (68.8)
25 (31.3) 55 (68.8)
x2
p-value
0.71
0.5a
7.17
0.07
5.63
0.03a,*
1.25
0.54
3.45
0.09a
7.32
0.01a,*
3.64
0.08a
1.66
0.44
2.8
0.25
0.27
0.73a
0
1a
Fisher's exact test. p < 0.05.
Please cite this article in press as: S.-Y. Wen, et al., Sleep quality at 3 months postpartum considering maternal age: A comparative study, Women Birth (2018), https://doi.org/10.1016/j.wombi.2018.02.004
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no significant differences between the two age groups in the included characteristics, except for family socio-economic status and preterm birth. A comparison of sleep quality between women younger and older than 35 years of age is shown in Table 2. Prevalence of poor sleep quality (PSQI 5) was 66.25% among the mothers aged 35 years and 41.25% among the younger mothers (p = 0.002). The PSQI total score for the advanced age group was 6.85 (SD 3.21) compared to 5.48 (SD 3.22) for the non-advanced age group (p < 0.05). Women with advanced age scored significantly higher than those with non-advanced age in the two subscales measuring sleep efficiency and sleep disturbance. The severity of postpartum physical symptoms was compared between women in the two age groups (Table 3). The mean overall PPSC scores were not significantly different between the advanced age (mean = 4.03, SD = 3.11) and non-advanced age groups (mean = 4.65, SD = 3.49; p = 0.23). For the individual items of the PPSC, only one item, namely the “caesarean section wound or perineal pain”, was significantly higher in the advanced age group than in the nonadvanced age group. No significant differences were observed between the two groups in the other items. Crude and adjusted ORs from the logistic regression were presented in Table 4. Of all the variables included (as in the Measurements section), advanced maternal age, sleeping arrangement for the infants, exercise, and postpartum physical symptoms severity were significantly associated with poor sleep quality. Those women in the advanced age group were more likely to have poor sleep quality than younger mothers (crude OR = 2.79, 95% CI: 1.47 – 5.32, p = 0.002). All other variables were not significantly
associated with poor sleep quality and thus were not included in the multivariate analysis. The results of the multiple logistic regression revealed that women in the advanced age group were more likely to have poor sleep quality (OR = 3.08, 95% CI 1.52–6.23; Table 4). Compared with women who did not share a room or bed with their infants, women who shared the room with their infants without bed-sharing was significantly associated with increased odds for poor sleep quality (OR = 4.20, 95% CI 1.05–16.70, p = 0.04), while sharing the bed with their infants was not statistically significantly associated with poor sleep quality (OR = 3.95, 95% CI 0.99–15.83, p = 0.05). Women who did not exercise during the past 2 weeks were more likely to have poor sleep quality (OR = 2.26, 95% CI 1.06–4.83, p = 0.04). Furthermore, the severities of postpartum physical symptoms were positively associated with poor sleep quality (OR = 1.24, 95% CI 1.09–1.41, p = 0.001) with each point increase in the PPSC score being associated with 1.24 times of odds for poor sleep quality. 4. Discussion The present study demonstrated that women older than 35 years of age were three times more likely to have poor sleep quality than younger women at 3 months postpartum, while adjusting for the severity of postpartum physical symptoms, socio-demographics, obstetrical history, and health behaviours. The increased risk of poor sleep quality may be related to the natural ageing. A previous study among adults 31–44 years of age revealed that the time of sleep onset was significantly longer in men and women as they grew older, and started to increase significantly at 37 years of
Table 2 Comparison of sleep quality between women younger or older than 35 years (n = 160).
Subjective sleep quality Very good Fairly good Fairly bad Very bad Sleep latency 15 min 16–30 min 31–59 min 60 min Sleep duration >7 h 6–7 h 5 to <6 h <5 h Sleep efficiency 85% 75% to <85% 65% to <75% <65% Sleep disturbance 0 1–9 10–18 19–27 Daytime dysfunction 0 1–2 3–4 5–6 Use of sleeping medication None PSQI 5 Total score (0–21); M(SD)
Non-advanced age n (%) n = 80
Advanced age n (%) n = 80
10 (12.5) 44 (55.0) 22 (27.5) 4 (5.0)
11 (13.8) 35 (43.8) 26 (32.5) 8 (10.0)
57 (71.3) 18 (22.5) 3 (3.8) 2 (2.5)
64 (80.0) 12 (15.0) 3 (3.8) 1 (1.3)
24 (30.0) 25 (31.3) 15 (18.8) 16 (20.0)
13 (16.3) 20 (25.0) 24 (30.0) 23 (28.8)
45 (56.3) 9 (11.3) 12 (15.0) 14 (17.5)
22 (27.5) 26 (32.5) 9 (11.3) 23 (28.8)
25 (31.3) 50 (62.5) 5 (6.3) 0 (0)
13 (16.3) 55 (68.8) 9 (11.3) 3 (3.8)
35 (43.8) 24 (30.0) 15 (18.8) 6 (7.5)
33 (41.3) 25 (31.3) 13 (16.3) 9 (11.3)
80 (100) 33 (41.3) 5.48 (3.22)
80 (100) 53 (66.3) 6.85 (3.21)
X2/t
p-value
2.74
0.43
1.94
0.59
7.16
0.067
8.77
0.001*
8.17
0.043*
0.82
0.84
10.06 2.7
– 0.002 0.008*
PSQI, Pittsburgh Sleep Quality Index. * p < 0.05.
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Table 3 Comparison of severity of postpartum physical symptoms between women younger or older than 35 years of age (n = 160).
Caesarean section wound or perineal pain Constipation Backache Headache Haemorrhoids Joint pain Numbness in the hands Excessive leucorrhoea Vaginal infection Numbness in the feet Urinary-tract infection Excessive vaginal bleeding Dizziness Varicose vein over legs Urinary incontinence Higher incidence of cold than usual Cold hands and/or feet Total score (range 0–51); M(SD)
Non-advanced age (n = 80) Mean (SD)
Advanced age (n = 80) Mean (SD)
t-value
p-value
0.01 (0.11) 0.39 (0.74) 0.86 (0.76) 0.16 (0.51) 0.31 (0.59) 0.35 (0.73) 0.3 (0.6) 0.25 (0.49) 0.0 (0.0) 0.15 (0.45) 0.0 (0.0) 0.0 (0.0) 0.28 (0.53) 0.31 (0.52) 0.09 (0.28) 0.18 (0.41) 0.06 (0.33) 4.65 (3.49)
0.15 (0.42) 0.31 (0.65) 0.93 (0.94) 0.33 (0.59) 0.39 (0.61) 0.43 (0.73) 0.15 (0.42) 0.16 (0.4) 0.03 (0.22) 0.19 (0.5) 0.03 (0.22) 0.03 (0.16) 0.23 (0.48) 0.24 (0.46) 0.13 (0.37) 0.34 (0.73) 0.06 (0.29) 4.03 (3.11)
2.81 0.68 0.46 1.86 0.80 0.625 1.82 1.23 1.0 0.49 1.0 1.42 0.63 0.97 0.72 1.74 0.00 1.20
0.006* 0.49 0.65 0.065 0.43 0.52 0.07 0.22 0.32 0.622 0.32 0.16 0.53 0.33 0.47 0.085 1.0 0.23
The item score ranges from 0 (none), 1 (mild), 2 (moderate), and 3 (severe). * p < 0.05; SD, standard deviation.
Table 4 Logistic regression models for poor sleep quality (n = 160). Crude results OR Non-advanced age group Advanced age group Sleeping arrangement for infants Not sharing the room or the bed Sharing the room, not the bed Sharing the bed Exercise Yes No Postpartum physical symptoms severity
Adjusted results 95% CI
p-value
OR
95% CI
p-value
1.52–6.23
0.002*
1.0 2.79
1.47–5.32
0.002*
1.0 3.08
1.0 3.24 3.17
0.93–11.21 0.9–11.1
0.06 0.07
1.0 4.20 3.95
1.05–16.70 0.99–15.83
0.04* 0.05
1.0 2.25 1.23
1.14–4.45 1.09–1.38
0.02* 0.001*
1.0 2.26 1.24
1.06–4.83 1.09–1.41
0.04* 0.001*
CI, confidence interval; OR, odds ratio. Postpartum physical symptoms severity was used as a continuous scale in the model. * p < 0.05.
age.21 A Norwegian study reported that sleep problems and fatigue were more common among pregnant women with their first baby at an advanced age (33–37 years) and very advanced age (38 years) than younger women (25–32 years).22 Our present findings extend previous results by demonstrating that advanced maternal age is associated with increased poor sleep quality at postpartum. Given the increasing trend of women giving birth at a late age, health professionals need to be aware of the increased risk of poor sleep quality and should provide suitable advices. In terms of the multiple dimensions of the PSQI, mothers of advanced age scored significantly higher in sleep efficiency and sleep disturbance, but not in the other dimensions. Sleep efficiency is the ratio of the total time spent asleep (total sleep time) over one night divided by the total amount of time spent in bed. Sleep disturbance includes among others the awakening in the mid of sleep, difficulties in initiating sleep, nightmares, and pain. Based on our findings, the mothers over 35 years of age were more likely to have fragmented sleep and difficulties in falling asleep once their sleep was interrupted. Thus, relevant advice such as establishing a soothing pre-sleep routine, keeping a consistent sleep schedule, and not forcing oneself to go back to sleep may be helpful. Using a PSQI cut-off score of 5, the study found that more than 65% of women older than 35 years and 41.3% of women younger than 35 years had poor sleep quality. The results were consistent with previous findings whereby poor sleep quality was
demonstrated to be prevalent among postpartum women.23 Since poor sleep quality could cause fatigue and emotional disturbance among mothers, which could in turn influence parenting and infant health, strategies to improve sleep quality among mothers should be developed. For example, nonpharmacological behavioural interventions24 or alternative therapies such as back massage15 or aroma therapy25 could be provided to women with sleep problems. The severity of postpartum physical symptoms was significantly and positively related to poor sleep quality. Health professionals could provide care to alleviate the postpartum physical symptoms and teach women management skills in order to improve their sleep quality and well-being. Although the severity of postpartum physical symptoms did not differ significantly by age, the caesarean section and perineal pain were more severe among mothers with advanced age. We did not have data on perineal trauma and episiotomy among the study women. Nonetheless, the rate of episiotomy was high in Taiwan according to our clinical observation. Future study is needed to further discern the pain from caesarean section, episiotomy, or perineal trauma between mothers with or without advanced age in order to make more meaningful inference. In addition, the most severe physical symptom among new mothers was backache, which did not differ significantly between older and younger mothers. Taken together, these findings indicate that instructing mothers to manage pains
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related to backache or birth wound may help improve the quality of their sleep. We found that mothers who exercised had a better sleep quality than mothers who did not exercise. The finding was consistent with previous studies.24 Nonetheless, less than one-third (31.3%) of the mothers recruited in this study had exercised during the past 2 weeks. Health professionals should thus encourage mothers to exercise. The potential strategies could include infant care arrangement and exercise support for mothers.24,26 In their recommendations for a safe infant sleeping environment, the American Academy of Pediatrics and Taiwan Pediatric Association assert that room-sharing without bed-sharing is the best approach to decrease the risk of sudden infant death syndrome.27,28 Despite this recommendation, more than 40% of mothers shared the bed with their infants in our study. Parents should be advised of the risk of suffocation, strangulation, and entrapment that might occur when the infant is sleeping in an adult bed. We found that room-sharing with the infant, regardless of bed-sharing, was associated with an increased risk of poor sleep quality among mothers. Only less than 9% of mothers did not share the room with the infants among our study participants. Although room-sharing was a factor for poor sleep quality among mothers, room-sharing without bed-sharing should still be recommended for infants, owing to its protective effect against sudden infant death syndrome. Previous studies reported that night-time exclusive breastfeeding was associated with more nocturnal sleep among postpartum mothers.29,30 We did not find any significant effect of breastfeeding on the sleep quality in this study. These discrepancies could be due to the fact that most of the Taiwanese mothers used bottled breast milk to feed their infants, in contrast to previous studies where most breastfeeding mothers breastfed their infants during the night. Further studies are still needed to examine the effect of using bottled milk or breastfeeding on sleep quality among exclusive breastfeeding mothers. Several limitations should be acknowledged in the present study. First, sleep quality measurement in our study was based on self-reports, which are not as accurate as objective measurement methods. Second, the samples were from one regional teaching hospital, and the results might thus not be representative of the general population. Third, the present study followed a crosssectional design, and the relationship reported was thus correlational, but not causal. Fourth, in measuring the postpartum physical symptoms severity, we deleted one item (poor sleep quality) because it overlapped with the dependent variable. Though deletion of this one item did not change the internal consistency significantly in the study, the low internal consistency of the scale in this study may be a concern. The low internal consistency could be associated with the fact that the severity of postpartum physical symptoms was generally low in our study participants (Table 3). Further validation of the PPSC among postpartum population may be needed. Fifth, the confidence interval for sleeping arrangement for infants was wide due to the fact that only 14 mothers did not share the room with their infants. The finding may need to be confirmed in studies with larger sample size. Sixth, we did not collect data on smoking, alcohol or substance use, obesity, and room/bed sharing with partners or other children. Those unmeasured factors could have confounded our results. Seventh, age of the study women ranged from 23.6 to 44.3 years. Studies with wider age range samples may be warranted in future studies. 5. Conclusions The present study demonstrated that poor sleep quality was prevalent among new mothers. In addition, poor sleep quality was
significantly higher among mothers aged over 35 years than among mothers younger than 35 years of age at 3 months postpartum. Besides advanced age, lack of exercise, room-sharing with infants, and severity of postpartum physical symptoms were associated with an increased risk for poor sleep quality. The present findings suggested that health professionals should provide strategies to improve sleep quality among new mothers, with special emphasis on mothers of advanced age. Management of postpartum physical symptoms and encouraging mothers to exercise could be effective strategies. Ethical statement The study protocol has been approved by the Taiwan Adventist Hospital Institutional Review Board (No. 103-E-01). Date of approval was February 20, 2014. Conflict of interest The authors declare no conflict of interest involved with this study. Acknowledgements No financial assistance with the project has been received. The authors would like to thank the study participants for their participation. References 1. Department of Statistics, Ministry of the Interior (Taiwan). Monthly bulletin of interior statistics. May 14, 2017 Available from: http://www.moi.gov.tw/stat/ news_content.aspx?sn=10640. 2. National Statistics, R.O.C. (Taiwan). Social indicators. 2013 Available from: https://eng.stat.gov.tw/public/Attachment/41018441CA7EAUC2.pdf. 3. Chien LY, Tai CJ, Ko YL, Huang CH, Sheu SJ. Adherence to “doing-the-month” practices is associated with fewer physical and depressive symptoms among postpartum women in Taiwan. Res Nurs Health 2006;29(October (5)):374–83. 4. Cleary-Goldman J, Malone FD, Vidaver J, Ball RH, Nyberg DA, Comstock CH, et al. Impact of maternal age on obstetric outcome. Obstet Gynecol 2005;105(5 Pt 1):983–90. 5. Okun ML, Roberts JM, Marsland AL, Hall M. How disturbed sleep may be a risk factor for adverse pregnancy outcomes. Obstet Gynecol Surv 2009;64(April (4)):273–80. 6. Mori E, Iwata H, Sakajo A, Maehara K, Ozawa H, Maekawa T, et al. Postpartum experiences of older Japanese primiparas during the first month after childbirth. Int J Nurs Pract 2014;20(March (Suppl 1)):20–31. 7. Carolan M. Maternal and child health nurses: a vital link to the community for primiparae over the age of 35. Contemp Nurse 2004–2005;18(1-2):133–42. 8. Matsumoto K, Tsuchiya KJ, Itoh H, Kanayama N, Suda S, Matsuzaki H, et al. Agespecific 3-month cumulative incidence of postpartum depression: the Hamamatsu Birth Cohort (HBC) Study. J Affect Disord 2011;133(October (3)):607–10. 9. Nishihara K, Horiuchi S, Eto H, Uchida S. The development of infants’ circadian rest-activity rhythm and mothers’ rhythm. Physiol Behav 2002;77(September (1)):91–8. 10. Posmontier B. Sleep quality in women with and without postpartum depression. J Obstet Gynecol Neonatal Nurs 2008;37(November–December (6)):722–37. 11. Park EM, Meltzer-Brody S, Stickgold R. Poor sleep maintenance and subjective sleep quality are associated with postpartum maternal depression symptom severity. Arch Womens Ment Health 2013;16(December (6)):539–47. 12. Krawczak EM, Minuzzi L, Simpson W, Hidalgo MP, Frey BN. Sleep, daily activity rhythms and postpartum mood: a longitudinal study across the perinatal period. Chronobiol Int 2016;33(7):791–801. 13. Dørheim SK, Bondevik GT, Eberhard-Gran M, Bjorvatn B. Sleep and depression in postpartum women: a population-based study. Sleep 2009;32(July (7)):847–55. 14. Bei B, Milgrom J, Ericksen J, Trinder J. Subjective perception of sleep, but not its objective quality, is associated with immediate postpartum mood disturbances in healthy women. Sleep 2010;33(April (4)):531–8. 15. Ko YL, Lee HJ. Randomized controlled trial of the effectiveness of back massage to improve sleep quality among Taiwanese insomnia postpartum women. Midwifery 2014;30(January (1)):60–4. 16. Ohayon MM, Carskadon MA, Guilleminault C, Vitiello MV. Meta-analysis of quantitative sleep parameters from childhood to old age in healthy
Please cite this article in press as: S.-Y. Wen, et al., Sleep quality at 3 months postpartum considering maternal age: A comparative study, Women Birth (2018), https://doi.org/10.1016/j.wombi.2018.02.004
G Model WOMBI 772 No. of Pages 7
S.-Y. Wen et al. / Women and Birth xxx (2018) xxx–xxx
17. 18. 19.
20. 21.
22.
23.
individuals: developing normative sleep values across the human lifespan. Sleep 2004;27(November (7)):1255–73. Teng FL, See LC, Cheng PJ, Lee JT. The quality of sleep and its associated factors in the puerperium women. Chang Gung Nurs 2007;18(4):499–510. Hollingshead AB. Two factor index of social position. New Haven, Connecticut: Yale University Press; 1957. Buysse DJ, Reynolds CF, Monk TH, Berman SR, Kupfer DJ. The Pittsburgh Sleep Quality Index: a new instrument for psychiatric practice and research. Psychiatry Res 1989;28(May (2)):193–213. Su TP. Classification of sleep disorders and clinical assessment. J Formos Med Assoc 2000;4:665–72. Tonetti L, Fabbri M, Natale V. Sex difference in sleep-time preference and sleep need: a cross-sectional survey among Italian pre-adolescents, adolescents, and adults. Chronobiol Int 2008;25(September (5)):745–59. Nilsen AB, Waldenstrom U, Hjelmsted A, Rasmussen S, Schytt E. Characteristics of women who are pregnant with their first baby at an advanced age. Acta Obstet Gynecol Scand 2012;91(March (3)):353–62. Tsai SY, Thomas KA. Sleep disturbances and depressive symptoms in healthy postpartum women: a pilot study. Res Nurs Health 2012;35(June (3)):314–23.
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24. Ashrafinia F, Mirmohammadali M, Rajabi H, Kazemnejad A, Sadeghniiathaghighi K, Amelvalizadeh M, et al. The effects of Pilates exercise on sleep quality in postpartum women. J Bodyw Mov Ther 2014;18(April (2)):190–9. 25. Hwang E, Shin S. The effects of aromatherapy on sleep improvement: a systematic literature review and meta-analysis. J Altern Complement Med 2015;21(February (2)):61–8. 26. Rudzik AE, Ball HL. Exploring maternal perceptions of infant sleep and feeding method among mothers in the United Kingdom: a qualitative focus group study. Matern Child Health J 2016;20(January (1)):33–40. 27. American Academy of Pediatrics. SIDS and other sleep-related infant deaths: expansion of recommendations for a safe infant sleeping environment. Pediatrics 2011;128:1030–9. 28. Taiwan Pediatric Association. Recommendations for prevention of sudden infant death syndrome. Available from: http://www.pediatr.org.tw/people/ edu_info.asp?id=14. 29. Doan T, Gay CL, Kennedy HP, Newman J, Lee KA. Nighttime breastfeeding behavior is associated with more nocturnal sleep among first-time mothers at one month postpartum. J Clin Sleep Med 2014;10(March (3)):313–9. 30. Doan T, Gardiner A, Gay CL, Lee KA. Breast-feeding increases sleep duration of new parents. J Perinat Neonatal Nurs 2007;21(July–September (3)):200–6.
Please cite this article in press as: S.-Y. Wen, et al., Sleep quality at 3 months postpartum considering maternal age: A comparative study, Women Birth (2018), https://doi.org/10.1016/j.wombi.2018.02.004
Women and Birth xxx (2018) xxx–xxx
Contents lists available at ScienceDirect
Women and Birth journal homepage: www.elsevier.com/locate/wombi
Original Research - Quantitative
Sleep quality at 3 months postpartum considering maternal age: A comparative study Shih-Yi Wena , Yi-Li Kob , Hei-Jen Jouc , Li-Yin Chiend,* a
Department of Obstetrics and Gynecology, Fu Jen Catholic University Hospital, New Taipei City, Taiwan Department of Nursing, Fu Jen Catholic University, New Taipei City 24205, Taiwan c Department of Obstetrics and Gynecology, Taiwan Adventist Hospital, Taipei, Taiwan d Institute of Community Health Care, National Yang-Ming University, Taipei, Taiwan b
A R T I C L E I N F O
A B S T R A C T
Article history: Received 2 October 2017 Received in revised form 5 February 2018 Accepted 9 February 2018 Available online xxx
Background: Poor sleep quality is related to old age among the general population, but few studies have focused on postpartum women of advanced maternal age. The present study aimed to describe and compare sleep quality between women younger or older than 35 years of age at 3 months postpartum, and to examine the related factors. Methods: A cross-sectional survey was conducted with 160 postpartum women who had given birth at a teaching hospital in Taiwan. The participants were assigned to two groups according to age (35 years, n = 80; and 20–34 years, n = 80). Sleep quality was measured using the Pittsburgh Sleep Quality Index with a cut-off score of 5. Results: The prevalence of poor sleep quality at 3 months postpartum was higher in older mothers (61.6%) than in younger mothers (38.4%, p < 0.01). Multiple logistic regression revealed that poor sleep quality was positively correlated with the severity of postpartum physical symptoms, lack of exercise, and roomsharing with infants. After adjustment for those variables, older mothers were three times more likely to have poor sleep quality than younger mothers (odds ratio = 3.08; 95% confidence interval 1.52–6.23). Conclusion: Health care providers should pay attention to sleep problems among postpartum women, especially mothers of advanced maternal age. In particular, health care providers should evaluate sleep quality among postpartum women, instruct them not to share the bed with their infants at night, perform exercise, and manage their postpartum physical symptoms to improve the sleep quality. © 2018 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.
Keywords: Sleep Postpartum period Sleep quality Maternal age Maternal health
Statement of significance
Problem Advanced maternal age has become more common in modern society, however, its’ association with postpartum sleep quality remained unclear.
What this paper adds Mothers 35 years of age were three times more likely to have poor sleep quality than younger mothers after adjustment for the three factors that were significantly positively associated with poor sleep quality; severity of postpartum physical symptoms, lack of exercise, and roomsharing with infants.
What is already known Poor sleep quality is common among postpartum women. Factors related to poor sleep quality included sociodemographics, obstetrical history, infant care, personal health history and symptoms, and lifestyle factors.
* Corresponding author at: 155 Li-Nong Street, Sec. 2, Bei-Tou, Taipei 11221, Taiwan. E-mail address: [email protected] (L.-Y. Chien).
1. Introduction Advanced maternal age has recently become more common in Taiwan. Between 2006 and 2016, the proportion of primiparous women aged 35 years or older increased from 33.05% to 36.73%,1 and the mean maternal age at birth increased from 30.9 years in 20132 to 31.9 years in 2016.1 Childbearing at an advanced maternal age is a growing clinical concern because women with advanced maternal age have generally high-risk pregnancies and births.3–5
https://doi.org/10.1016/j.wombi.2018.02.004 1871-5192/© 2018 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.
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Indeed, advanced maternal age was associated with an increased risk of pregnancy complications, caesarean births, preterm births, and postpartum physical symptoms.3–5 In addition, older mothers may demonstrate several physical and psychosocial characteristics or limitations, such as poor physical strength6 and limited social support.7 Those factors may interfere with maternal adaptation after childbirth. Advanced maternal age has also been associated with postpartum depression, particularly in primiparous women.8 In the postpartum period, infants typically require frequent feedings at night that result in frequent waking after sleep onset, reduced sleep duration, and reduced time of asleep in night among mothers.9 Sleep disturbance is an important health issue in postpartum women, because of its association with fatigue, depression, and emotional disturbance.10–12 Previous studies on subjective sleep quality in postpartum women using Pittsburgh Sleep Postnatal Depression Scale (PSQI)13–15 indicated that the sleep quality is disrupted immediately after childbirth, followed by an improvement; however, it remains a problem during the first 2–3 months postpartum for many women. In addition, the sleep quality has been reported to decline with age in adults.16 However, most previous studies have focused on sleep quality among young postpartum women, and only few studies reported on postpartum sleep quality in mothers with advanced maternal age. The objectives of the present study were to describe and compare sleep quality between women 20–34 years or 35 years of age at 3 months postpartum, and to examine the related factors in Taipei City, Taiwan. 2. Participants, ethics, and methods 2.1. Sample size estimation Based on results of a previous study,17 we hypothesised that the effect size of differences in sleep quality between women with and without advanced maternal age was 0.5. Using G power 3.1.7, the required sample size was 64 per group when effect size was 0.5, two-sided a was 0.05, and power was 0.8. To account for rejection and missing data, we decided to recruit 80 women each for women with and without advanced maternal age. 2.2. Design and participants In this cross-sectional survey, we recruited women who hospitalized at a postpartum ward of a regional teaching hospital in Taipei, Taiwan. The inclusion criteria were adult women (20 years of age) without severe maternal or neonatal complications and who can communicate in Mandarin Chinese or Taiwanese. During the period between February 2014 and December 2014, the first author assessed eligibility of the study participants at the ward every 3 days. She approached women who were eligible to be enrolled in the study and explained the study purpose to ask whether the women agreed to participate and to be telephoneinterviewed about 3 months later. The recruitment was conducted in a consecutive of presentations to the hospital until the desired sample size and proportion of parity was reached. In accordance with the requirement of the institutional review board at the study hospital, those women who agreed to participate signed a consent form and left their contact phone number to the first author. Of the 183 women approached, 23 refused to participate in the study. In total, 160 postpartum women were enrolled, of whom 80 were aged 35 years or older (advanced age group) and 80 were aged 20– 34 years (non-advanced age group). The two groups were frequency-matched for parity. Since half of the women in the advanced age group were primiparous (n = 40) and the remaining were multiparous (n = 40), we recruited the same proportion of parity in the non-advanced age group. The study participants were
interviewed by the first author using structured questionnaires at 12–14 weeks postpartum during 15 to 20-min telephone interviews from May 2014 through February 2015. This study was approved by the institutional review board at the Taiwan Adventist Hospital (No. 103-E-01). 2.3. Measurements Based on literature review and clinical observations, we designed the study tool. The study tools included the following: (1) a self-designed structured questionnaire, which comprised basic information and pregnancy/childbirth history, healthy life style, and newborn care variables; (2) the Postpartum Physical Symptoms Checklist (PPSC); and (3) the Pittsburgh Sleep Quality Index (PSQI). The basic information included age, work status, education level, and family socio-economic status. The family socioeconomic status was determined based on the Hollingshead 2factor index of social position. The highest level of education and occupation of each couple were used to calculate the index based on the following equation: (education level 4) + (occupational level 7). The index was divided into high (41–55), middle (30– 40), and low (11–29) groups.18 The obstetrical history included parity, birth mode, preterm birth, and infant sex. The personal lifestyle included the behaviour of coffee/tea drinking and exercise in the past 2 weeks. The newborn care variables included the infant feeding method and sleeping arrangements for the baby. Content validity of the self-designed structured questionnaire was reviewed by 5 experts, including 2 obstetricians, 1 clinical nursing instructor, 1 nursing professor, and 1 deputy head nurse of postpartum ward. The experts rated the appropriateness of the questions on a 5-point Likert-scale (from 1 to 5) and provided feedback on revising the question if a question received a score of <3. The content validity index was 0.98, i.e., 98% of the questions received a score of 3. The PPSC was designed to measure the severity of postpartum physical symptoms among postpartum women.3 The original checklist contained 18 common postpartum physical symptoms, including caesarean section wound or perineal pain, constipation, backache, headache, haemorrhoids, joint pain, numbness in the hands, excessive leucorrhoea, vaginal infection, numbness in the feet, urinary-tract infection, excessive vaginal bleeding, dizziness, varicose vein over legs, urinary incontinence, a higher incidence of cold than usual, and cold hands and/or feet. The content validity of the PPSC had been established through experts review. The internal consistency of the scale as assessed by Cronbach's a among women at one month postpartum in Taiwan was 0.77.3 We deleted one item in this study, namely the poor sleep quality, because it overlapped with the dependent variable. A 4-point Likert-scale ranging from 0 to 3 (none, mild, moderate, severe) was applied to each item in the PPSC, for a total scale range of 0–51 points, with higher scores suggesting severer physical symptoms. The internal consistency of the scale as assessed by Cronbach's a was 0.56 for the 18 items and 0.54 for the 17 items (deleting poor sleep quality) in this study. Sleep quality was measured using the PSQI,19 which consisted of seven sleep components: subjective sleep quality, sleep latency, sleep duration, sleep efficiency, sleep disturbance, day-time dysfunction, and use of sleeping medication. Items were measured using a 4-point Likert-scale ranging from 0 to 3. The sum of the seven component scores formed a global PSQI score (range 0–21), with higher scores indicating a poorer quality of sleep. A cut-off score of 5 was used to demarcate good sleepers from poor sleepers. The PSQI was previously shown to be a reliable and valid tool in measuring quality of sleep.19 The PSQI was translated into Chinese
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and back-translated into English by bilingual people with bicultural experience to establish content and semantic equivalence.20 The PSQI has been used to measure sleep quality among perinatal and postpartum women in many previous studies.13–15 Internal consistency (Cronbach's a) for the Chinese PSQI was assessed at 0.73 in this study. 2.4. Data analysis Descriptive analyses were performed by calculating frequencies, percentages, means, and standard deviations (SD). Pearson's chi-squared tests or Fisher's exact tests were used to examine differences in characteristics between women of the two age groups. Fisher's exact tests were used when at least one cell of the table had an expected count smaller than 5. Multiple logistic regression analysis was used to identify factors related to poor sleep quality and to examine the net effect of advanced maternal age on poor sleep quality given that other variables in the model were adjusted for. We started with a model for poor sleep quality with only advanced age as the independent variable. Then, in forward stepwise selections, we added independent variables that were significantly related to breastfeeding. The final logistic regression model included all significant variables (two-sided pvalue < 0.05) and estimated adjusted odds ratios of the included variables. Data analysis was performed using the Statistical
3
Package for the Social Sciences (SPSS) for Windows version 18.0 (SPSS Inc, Chicago, Illinois). 3. Results Of the 160 participants recruited, 80 were aged 35 years or more (advanced maternal age; mean age, 37.2 1.8 years; range 23.6–34.9 years) and 80 were younger than 35 years of age (nonadvanced maternal age; mean age, 31.7 2.7 years; range 35.1– 44.3 years). Characteristics between participants with advanced and non-advanced maternal age were compared in Table 1. Half of the participants in each age group were primipara. The mothers were predominantly college or university educated (68%), and the majority was employed (67%). Most birth modes were vaginal (76%) and most mothers practiced mixed formula feeding and breastfeeding (82%). Mothers of the advanced age group had higher social economic status (60%) than those of the non-advanced age group (41.3%; p = 0.030). The rate of preterm birth was higher (8.8%) in the advanced age group than in the non-advanced age group (0%; p = 0.01). Approximately 48.8% of the mothers were room-sharing, but not bed-sharing, with their infants, 42.5% were bed-sharing with their infants, and only 8.8% did not share the room or bed with their infants. Approximately 70% of the mothers drank tea or coffee, while only 31% of mothers reported exercise in the past 2 weeks. There were
Table 1 Characteristics of the study participants (n = 160). Characteristics
Work status No Yes Education level High school or below Vocational school University or collage Graduate school Family socio-economic status Middle or low High Parity 1 2 3 Birth mode Vaginal Caesarean Preterm birth No Yes Infant sex Male Female Sleeping arrangements for infants Sharing room, not bed Sharing bed None Infant feeding Exclusive breastfeeding Mixed feeding Formula Coffee/tea drinking (past 2 weeks) Yes No Exercise (past 2 weeks) Yes No a *
Non-advanced age n (%) n = 80
Advanced age n (%) n = 80
29 (36.3) 51 (63.8)
24 (30.0) 56 (70.0)
6 (7.5) 8 (10) 52 (65.0) 14 (17.4)
4 (5.0) 11 (13.8) 38 (47.5) 27 (33.8)
47 (58.8) 33 (41.3)
32 (40.0) 48 (60.0)
40 (50.0) 34 (42.5) 6 (7.5)
40 (50.0) 30 (37.5) 10 (12.5)
66 (82.5) 14 (17.5)
56 (70.0) 24 (30.0)
80 (100) 0 (0)
73 (91.3) 7 (8.8)
30 (37.5) 50 (62.5)
42 (52.5) 38 (47.5)
42 (53.8) 33 (41.2) 5 (6.2)
36 (46.2) 35 (43.8) 9 (11.3)
41 (51.3) 25 (31.3) 14 (17.5)
31 (38.8) 34 (42.5) 15 (18.8)
55 (68.8) 25 (31.3)
58 (72.5) 22 (27.5)
25 (31.3) 55 (68.8)
25 (31.3) 55 (68.8)
x2
p-value
0.71
0.5a
7.17
0.07
5.63
0.03a,*
1.25
0.54
3.45
0.09a
7.32
0.01a,*
3.64
0.08a
1.66
0.44
2.8
0.25
0.27
0.73a
0
1a
Fisher's exact test. p < 0.05.
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no significant differences between the two age groups in the included characteristics, except for family socio-economic status and preterm birth. A comparison of sleep quality between women younger and older than 35 years of age is shown in Table 2. Prevalence of poor sleep quality (PSQI 5) was 66.25% among the mothers aged 35 years and 41.25% among the younger mothers (p = 0.002). The PSQI total score for the advanced age group was 6.85 (SD 3.21) compared to 5.48 (SD 3.22) for the non-advanced age group (p < 0.05). Women with advanced age scored significantly higher than those with non-advanced age in the two subscales measuring sleep efficiency and sleep disturbance. The severity of postpartum physical symptoms was compared between women in the two age groups (Table 3). The mean overall PPSC scores were not significantly different between the advanced age (mean = 4.03, SD = 3.11) and non-advanced age groups (mean = 4.65, SD = 3.49; p = 0.23). For the individual items of the PPSC, only one item, namely the “caesarean section wound or perineal pain”, was significantly higher in the advanced age group than in the nonadvanced age group. No significant differences were observed between the two groups in the other items. Crude and adjusted ORs from the logistic regression were presented in Table 4. Of all the variables included (as in the Measurements section), advanced maternal age, sleeping arrangement for the infants, exercise, and postpartum physical symptoms severity were significantly associated with poor sleep quality. Those women in the advanced age group were more likely to have poor sleep quality than younger mothers (crude OR = 2.79, 95% CI: 1.47 – 5.32, p = 0.002). All other variables were not significantly
associated with poor sleep quality and thus were not included in the multivariate analysis. The results of the multiple logistic regression revealed that women in the advanced age group were more likely to have poor sleep quality (OR = 3.08, 95% CI 1.52–6.23; Table 4). Compared with women who did not share a room or bed with their infants, women who shared the room with their infants without bed-sharing was significantly associated with increased odds for poor sleep quality (OR = 4.20, 95% CI 1.05–16.70, p = 0.04), while sharing the bed with their infants was not statistically significantly associated with poor sleep quality (OR = 3.95, 95% CI 0.99–15.83, p = 0.05). Women who did not exercise during the past 2 weeks were more likely to have poor sleep quality (OR = 2.26, 95% CI 1.06–4.83, p = 0.04). Furthermore, the severities of postpartum physical symptoms were positively associated with poor sleep quality (OR = 1.24, 95% CI 1.09–1.41, p = 0.001) with each point increase in the PPSC score being associated with 1.24 times of odds for poor sleep quality. 4. Discussion The present study demonstrated that women older than 35 years of age were three times more likely to have poor sleep quality than younger women at 3 months postpartum, while adjusting for the severity of postpartum physical symptoms, socio-demographics, obstetrical history, and health behaviours. The increased risk of poor sleep quality may be related to the natural ageing. A previous study among adults 31–44 years of age revealed that the time of sleep onset was significantly longer in men and women as they grew older, and started to increase significantly at 37 years of
Table 2 Comparison of sleep quality between women younger or older than 35 years (n = 160).
Subjective sleep quality Very good Fairly good Fairly bad Very bad Sleep latency 15 min 16–30 min 31–59 min 60 min Sleep duration >7 h 6–7 h 5 to <6 h <5 h Sleep efficiency 85% 75% to <85% 65% to <75% <65% Sleep disturbance 0 1–9 10–18 19–27 Daytime dysfunction 0 1–2 3–4 5–6 Use of sleeping medication None PSQI 5 Total score (0–21); M(SD)
Non-advanced age n (%) n = 80
Advanced age n (%) n = 80
10 (12.5) 44 (55.0) 22 (27.5) 4 (5.0)
11 (13.8) 35 (43.8) 26 (32.5) 8 (10.0)
57 (71.3) 18 (22.5) 3 (3.8) 2 (2.5)
64 (80.0) 12 (15.0) 3 (3.8) 1 (1.3)
24 (30.0) 25 (31.3) 15 (18.8) 16 (20.0)
13 (16.3) 20 (25.0) 24 (30.0) 23 (28.8)
45 (56.3) 9 (11.3) 12 (15.0) 14 (17.5)
22 (27.5) 26 (32.5) 9 (11.3) 23 (28.8)
25 (31.3) 50 (62.5) 5 (6.3) 0 (0)
13 (16.3) 55 (68.8) 9 (11.3) 3 (3.8)
35 (43.8) 24 (30.0) 15 (18.8) 6 (7.5)
33 (41.3) 25 (31.3) 13 (16.3) 9 (11.3)
80 (100) 33 (41.3) 5.48 (3.22)
80 (100) 53 (66.3) 6.85 (3.21)
X2/t
p-value
2.74
0.43
1.94
0.59
7.16
0.067
8.77
0.001*
8.17
0.043*
0.82
0.84
10.06 2.7
– 0.002 0.008*
PSQI, Pittsburgh Sleep Quality Index. * p < 0.05.
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Table 3 Comparison of severity of postpartum physical symptoms between women younger or older than 35 years of age (n = 160).
Caesarean section wound or perineal pain Constipation Backache Headache Haemorrhoids Joint pain Numbness in the hands Excessive leucorrhoea Vaginal infection Numbness in the feet Urinary-tract infection Excessive vaginal bleeding Dizziness Varicose vein over legs Urinary incontinence Higher incidence of cold than usual Cold hands and/or feet Total score (range 0–51); M(SD)
Non-advanced age (n = 80) Mean (SD)
Advanced age (n = 80) Mean (SD)
t-value
p-value
0.01 (0.11) 0.39 (0.74) 0.86 (0.76) 0.16 (0.51) 0.31 (0.59) 0.35 (0.73) 0.3 (0.6) 0.25 (0.49) 0.0 (0.0) 0.15 (0.45) 0.0 (0.0) 0.0 (0.0) 0.28 (0.53) 0.31 (0.52) 0.09 (0.28) 0.18 (0.41) 0.06 (0.33) 4.65 (3.49)
0.15 (0.42) 0.31 (0.65) 0.93 (0.94) 0.33 (0.59) 0.39 (0.61) 0.43 (0.73) 0.15 (0.42) 0.16 (0.4) 0.03 (0.22) 0.19 (0.5) 0.03 (0.22) 0.03 (0.16) 0.23 (0.48) 0.24 (0.46) 0.13 (0.37) 0.34 (0.73) 0.06 (0.29) 4.03 (3.11)
2.81 0.68 0.46 1.86 0.80 0.625 1.82 1.23 1.0 0.49 1.0 1.42 0.63 0.97 0.72 1.74 0.00 1.20
0.006* 0.49 0.65 0.065 0.43 0.52 0.07 0.22 0.32 0.622 0.32 0.16 0.53 0.33 0.47 0.085 1.0 0.23
The item score ranges from 0 (none), 1 (mild), 2 (moderate), and 3 (severe). * p < 0.05; SD, standard deviation.
Table 4 Logistic regression models for poor sleep quality (n = 160). Crude results OR Non-advanced age group Advanced age group Sleeping arrangement for infants Not sharing the room or the bed Sharing the room, not the bed Sharing the bed Exercise Yes No Postpartum physical symptoms severity
Adjusted results 95% CI
p-value
OR
95% CI
p-value
1.52–6.23
0.002*
1.0 2.79
1.47–5.32
0.002*
1.0 3.08
1.0 3.24 3.17
0.93–11.21 0.9–11.1
0.06 0.07
1.0 4.20 3.95
1.05–16.70 0.99–15.83
0.04* 0.05
1.0 2.25 1.23
1.14–4.45 1.09–1.38
0.02* 0.001*
1.0 2.26 1.24
1.06–4.83 1.09–1.41
0.04* 0.001*
CI, confidence interval; OR, odds ratio. Postpartum physical symptoms severity was used as a continuous scale in the model. * p < 0.05.
age.21 A Norwegian study reported that sleep problems and fatigue were more common among pregnant women with their first baby at an advanced age (33–37 years) and very advanced age (38 years) than younger women (25–32 years).22 Our present findings extend previous results by demonstrating that advanced maternal age is associated with increased poor sleep quality at postpartum. Given the increasing trend of women giving birth at a late age, health professionals need to be aware of the increased risk of poor sleep quality and should provide suitable advices. In terms of the multiple dimensions of the PSQI, mothers of advanced age scored significantly higher in sleep efficiency and sleep disturbance, but not in the other dimensions. Sleep efficiency is the ratio of the total time spent asleep (total sleep time) over one night divided by the total amount of time spent in bed. Sleep disturbance includes among others the awakening in the mid of sleep, difficulties in initiating sleep, nightmares, and pain. Based on our findings, the mothers over 35 years of age were more likely to have fragmented sleep and difficulties in falling asleep once their sleep was interrupted. Thus, relevant advice such as establishing a soothing pre-sleep routine, keeping a consistent sleep schedule, and not forcing oneself to go back to sleep may be helpful. Using a PSQI cut-off score of 5, the study found that more than 65% of women older than 35 years and 41.3% of women younger than 35 years had poor sleep quality. The results were consistent with previous findings whereby poor sleep quality was
demonstrated to be prevalent among postpartum women.23 Since poor sleep quality could cause fatigue and emotional disturbance among mothers, which could in turn influence parenting and infant health, strategies to improve sleep quality among mothers should be developed. For example, nonpharmacological behavioural interventions24 or alternative therapies such as back massage15 or aroma therapy25 could be provided to women with sleep problems. The severity of postpartum physical symptoms was significantly and positively related to poor sleep quality. Health professionals could provide care to alleviate the postpartum physical symptoms and teach women management skills in order to improve their sleep quality and well-being. Although the severity of postpartum physical symptoms did not differ significantly by age, the caesarean section and perineal pain were more severe among mothers with advanced age. We did not have data on perineal trauma and episiotomy among the study women. Nonetheless, the rate of episiotomy was high in Taiwan according to our clinical observation. Future study is needed to further discern the pain from caesarean section, episiotomy, or perineal trauma between mothers with or without advanced age in order to make more meaningful inference. In addition, the most severe physical symptom among new mothers was backache, which did not differ significantly between older and younger mothers. Taken together, these findings indicate that instructing mothers to manage pains
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related to backache or birth wound may help improve the quality of their sleep. We found that mothers who exercised had a better sleep quality than mothers who did not exercise. The finding was consistent with previous studies.24 Nonetheless, less than one-third (31.3%) of the mothers recruited in this study had exercised during the past 2 weeks. Health professionals should thus encourage mothers to exercise. The potential strategies could include infant care arrangement and exercise support for mothers.24,26 In their recommendations for a safe infant sleeping environment, the American Academy of Pediatrics and Taiwan Pediatric Association assert that room-sharing without bed-sharing is the best approach to decrease the risk of sudden infant death syndrome.27,28 Despite this recommendation, more than 40% of mothers shared the bed with their infants in our study. Parents should be advised of the risk of suffocation, strangulation, and entrapment that might occur when the infant is sleeping in an adult bed. We found that room-sharing with the infant, regardless of bed-sharing, was associated with an increased risk of poor sleep quality among mothers. Only less than 9% of mothers did not share the room with the infants among our study participants. Although room-sharing was a factor for poor sleep quality among mothers, room-sharing without bed-sharing should still be recommended for infants, owing to its protective effect against sudden infant death syndrome. Previous studies reported that night-time exclusive breastfeeding was associated with more nocturnal sleep among postpartum mothers.29,30 We did not find any significant effect of breastfeeding on the sleep quality in this study. These discrepancies could be due to the fact that most of the Taiwanese mothers used bottled breast milk to feed their infants, in contrast to previous studies where most breastfeeding mothers breastfed their infants during the night. Further studies are still needed to examine the effect of using bottled milk or breastfeeding on sleep quality among exclusive breastfeeding mothers. Several limitations should be acknowledged in the present study. First, sleep quality measurement in our study was based on self-reports, which are not as accurate as objective measurement methods. Second, the samples were from one regional teaching hospital, and the results might thus not be representative of the general population. Third, the present study followed a crosssectional design, and the relationship reported was thus correlational, but not causal. Fourth, in measuring the postpartum physical symptoms severity, we deleted one item (poor sleep quality) because it overlapped with the dependent variable. Though deletion of this one item did not change the internal consistency significantly in the study, the low internal consistency of the scale in this study may be a concern. The low internal consistency could be associated with the fact that the severity of postpartum physical symptoms was generally low in our study participants (Table 3). Further validation of the PPSC among postpartum population may be needed. Fifth, the confidence interval for sleeping arrangement for infants was wide due to the fact that only 14 mothers did not share the room with their infants. The finding may need to be confirmed in studies with larger sample size. Sixth, we did not collect data on smoking, alcohol or substance use, obesity, and room/bed sharing with partners or other children. Those unmeasured factors could have confounded our results. Seventh, age of the study women ranged from 23.6 to 44.3 years. Studies with wider age range samples may be warranted in future studies. 5. Conclusions The present study demonstrated that poor sleep quality was prevalent among new mothers. In addition, poor sleep quality was
significantly higher among mothers aged over 35 years than among mothers younger than 35 years of age at 3 months postpartum. Besides advanced age, lack of exercise, room-sharing with infants, and severity of postpartum physical symptoms were associated with an increased risk for poor sleep quality. The present findings suggested that health professionals should provide strategies to improve sleep quality among new mothers, with special emphasis on mothers of advanced age. Management of postpartum physical symptoms and encouraging mothers to exercise could be effective strategies. Ethical statement The study protocol has been approved by the Taiwan Adventist Hospital Institutional Review Board (No. 103-E-01). Date of approval was February 20, 2014. Conflict of interest The authors declare no conflict of interest involved with this study. Acknowledgements No financial assistance with the project has been received. The authors would like to thank the study participants for their participation. References 1. Department of Statistics, Ministry of the Interior (Taiwan). Monthly bulletin of interior statistics. May 14, 2017 Available from: http://www.moi.gov.tw/stat/ news_content.aspx?sn=10640. 2. National Statistics, R.O.C. (Taiwan). Social indicators. 2013 Available from: https://eng.stat.gov.tw/public/Attachment/41018441CA7EAUC2.pdf. 3. Chien LY, Tai CJ, Ko YL, Huang CH, Sheu SJ. Adherence to “doing-the-month” practices is associated with fewer physical and depressive symptoms among postpartum women in Taiwan. Res Nurs Health 2006;29(October (5)):374–83. 4. Cleary-Goldman J, Malone FD, Vidaver J, Ball RH, Nyberg DA, Comstock CH, et al. Impact of maternal age on obstetric outcome. Obstet Gynecol 2005;105(5 Pt 1):983–90. 5. Okun ML, Roberts JM, Marsland AL, Hall M. How disturbed sleep may be a risk factor for adverse pregnancy outcomes. Obstet Gynecol Surv 2009;64(April (4)):273–80. 6. Mori E, Iwata H, Sakajo A, Maehara K, Ozawa H, Maekawa T, et al. Postpartum experiences of older Japanese primiparas during the first month after childbirth. Int J Nurs Pract 2014;20(March (Suppl 1)):20–31. 7. Carolan M. Maternal and child health nurses: a vital link to the community for primiparae over the age of 35. Contemp Nurse 2004–2005;18(1-2):133–42. 8. Matsumoto K, Tsuchiya KJ, Itoh H, Kanayama N, Suda S, Matsuzaki H, et al. Agespecific 3-month cumulative incidence of postpartum depression: the Hamamatsu Birth Cohort (HBC) Study. J Affect Disord 2011;133(October (3)):607–10. 9. Nishihara K, Horiuchi S, Eto H, Uchida S. The development of infants’ circadian rest-activity rhythm and mothers’ rhythm. Physiol Behav 2002;77(September (1)):91–8. 10. Posmontier B. Sleep quality in women with and without postpartum depression. J Obstet Gynecol Neonatal Nurs 2008;37(November–December (6)):722–37. 11. Park EM, Meltzer-Brody S, Stickgold R. Poor sleep maintenance and subjective sleep quality are associated with postpartum maternal depression symptom severity. Arch Womens Ment Health 2013;16(December (6)):539–47. 12. Krawczak EM, Minuzzi L, Simpson W, Hidalgo MP, Frey BN. Sleep, daily activity rhythms and postpartum mood: a longitudinal study across the perinatal period. Chronobiol Int 2016;33(7):791–801. 13. Dørheim SK, Bondevik GT, Eberhard-Gran M, Bjorvatn B. Sleep and depression in postpartum women: a population-based study. Sleep 2009;32(July (7)):847–55. 14. Bei B, Milgrom J, Ericksen J, Trinder J. Subjective perception of sleep, but not its objective quality, is associated with immediate postpartum mood disturbances in healthy women. Sleep 2010;33(April (4)):531–8. 15. Ko YL, Lee HJ. Randomized controlled trial of the effectiveness of back massage to improve sleep quality among Taiwanese insomnia postpartum women. Midwifery 2014;30(January (1)):60–4. 16. Ohayon MM, Carskadon MA, Guilleminault C, Vitiello MV. Meta-analysis of quantitative sleep parameters from childhood to old age in healthy
Please cite this article in press as: S.-Y. Wen, et al., Sleep quality at 3 months postpartum considering maternal age: A comparative study, Women Birth (2018), https://doi.org/10.1016/j.wombi.2018.02.004
G Model WOMBI 772 No. of Pages 7
S.-Y. Wen et al. / Women and Birth xxx (2018) xxx–xxx
17. 18. 19.
20. 21.
22.
23.
individuals: developing normative sleep values across the human lifespan. Sleep 2004;27(November (7)):1255–73. Teng FL, See LC, Cheng PJ, Lee JT. The quality of sleep and its associated factors in the puerperium women. Chang Gung Nurs 2007;18(4):499–510. Hollingshead AB. Two factor index of social position. New Haven, Connecticut: Yale University Press; 1957. Buysse DJ, Reynolds CF, Monk TH, Berman SR, Kupfer DJ. The Pittsburgh Sleep Quality Index: a new instrument for psychiatric practice and research. Psychiatry Res 1989;28(May (2)):193–213. Su TP. Classification of sleep disorders and clinical assessment. J Formos Med Assoc 2000;4:665–72. Tonetti L, Fabbri M, Natale V. Sex difference in sleep-time preference and sleep need: a cross-sectional survey among Italian pre-adolescents, adolescents, and adults. Chronobiol Int 2008;25(September (5)):745–59. Nilsen AB, Waldenstrom U, Hjelmsted A, Rasmussen S, Schytt E. Characteristics of women who are pregnant with their first baby at an advanced age. Acta Obstet Gynecol Scand 2012;91(March (3)):353–62. Tsai SY, Thomas KA. Sleep disturbances and depressive symptoms in healthy postpartum women: a pilot study. Res Nurs Health 2012;35(June (3)):314–23.
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24. Ashrafinia F, Mirmohammadali M, Rajabi H, Kazemnejad A, Sadeghniiathaghighi K, Amelvalizadeh M, et al. The effects of Pilates exercise on sleep quality in postpartum women. J Bodyw Mov Ther 2014;18(April (2)):190–9. 25. Hwang E, Shin S. The effects of aromatherapy on sleep improvement: a systematic literature review and meta-analysis. J Altern Complement Med 2015;21(February (2)):61–8. 26. Rudzik AE, Ball HL. Exploring maternal perceptions of infant sleep and feeding method among mothers in the United Kingdom: a qualitative focus group study. Matern Child Health J 2016;20(January (1)):33–40. 27. American Academy of Pediatrics. SIDS and other sleep-related infant deaths: expansion of recommendations for a safe infant sleeping environment. Pediatrics 2011;128:1030–9. 28. Taiwan Pediatric Association. Recommendations for prevention of sudden infant death syndrome. Available from: http://www.pediatr.org.tw/people/ edu_info.asp?id=14. 29. Doan T, Gay CL, Kennedy HP, Newman J, Lee KA. Nighttime breastfeeding behavior is associated with more nocturnal sleep among first-time mothers at one month postpartum. J Clin Sleep Med 2014;10(March (3)):313–9. 30. Doan T, Gardiner A, Gay CL, Lee KA. Breast-feeding increases sleep duration of new parents. J Perinat Neonatal Nurs 2007;21(July–September (3)):200–6.
Please cite this article in press as: S.-Y. Wen, et al., Sleep quality at 3 months postpartum considering maternal age: A comparative study, Women Birth (2018), https://doi.org/10.1016/j.wombi.2018.02.004