- Email: [email protected]
Obstetrical Complications in Pregnant Medical and Surgical Residents
OBSTETRICS
Obstetrical Complications in Pregnant Medical and Surgical Residents Sadikah Behbehani, MD, Togas Tulandi, MD, MHCM Department of Obstetrics and Gynecology, McGill University, Montreal QC
Abstract
Résumé
Objective: Pregnant residents are at risk for obstetrical complications. The purpose of our study was to evaluate the incidence and type of obstetrical complications of pregnancy during residency training, and their possible contributing factors.
Objectif : Les résidentes enceintes sont exposées à des risques de complications obstétricales. Notre étude avait pour objectif d’évaluer l’incidence et le type des complications obstétricales constatées dans le cadre de la résidence, ainsi que leurs facteurs contributifs possibles.
Method: We conducted a retrospective cohort study using a webbased questionnaire sent to 190 residency programs, both medical and surgical, across North America. The questionnaire was distributed to all female residents, and participants were asked to answer the questionnaire only if they had ever been pregnant. The questionnaire consisted of 10 multiple-choice questions and focused mainly on the complications that residents may have encountered during pregnancy before and during their residency training. The results were compared with those of 3767 pregnant women of similar age. Results: The rate of obstetrical complications among residents who had up to six nights on call per month (43/163 or 26.4%) was significantly lower than those who had more than six nights on call per month (37/75 or 49.3%) (P < 0.001). Among surgical residents, 16% performed over 40 hours of surgery per week. The rate of obstetrical complications among residents who had up to eight hours of operating room time per week (8.9%) was significantly lower than among residents who worked more than eight hours per week (41.7%) (P < 0.001). When we compared obstetrical complications among residents with those of women in the general population, we found that residents had higher rates of miscarriage, hypertension in pregnancy, placental abruption, and intrauterine growth restriction. Conclusion: Pregnancy during residency has a higher than average rate of adverse obstetrical outcomes. Longer operating hours and having more than six nights on call per month are associated with obstetrical complications. In addition, pregnant residents are more likely to have hypertensive disorders of pregnancy, intrauterine growth restriction, placental abruption, and miscarriages than a cohort of pregnant women of similar age.
Key Words: Pregnancy complications, residency training, medical resident, surgical resident
Méthodes : Nous avons mené une étude de cohorte rétrospective au moyen d’un questionnaire Web que nous avons fait parvenir à 190 programmes de résidence, tant en médecine qu’en chirurgie, de partout en Amérique du Nord. Ce questionnaire a été distribué à toutes les résidentes et nous avons demandé aux participantes de ne remplir le questionnaire que si elles avaient déjà connu une grossesse. Le questionnaire comptait 10 questions à choix multiple et était principalement axé sur les complications de grossesse auxquelles les résidentes pourraient avoir eu à faire face avant et pendant leur résidence. Les résultats ont été comparés à ceux qui ont été obtenus par 3 767 femmes enceintes d’âge semblable. Résultats : Le taux de complications obstétricales chez les résidentes qui étaient de garde pendant jusqu’à six nuits par mois (43/163 ou 26,4 %) était considérablement inférieur à celui des résidentes qui étaient de garde pendant plus de six nuits par mois (37/75 ou 49,3 %) (P < 0,001). Parmi les résidentes en chirurgie, 16 % menaient plus de 40 heures de chirurgie par semaine. Le taux de complications obstétricales chez les résidentes qui cumulaient jusqu’à huit heures en salle d’opération par semaine (8,9 %) était considérablement inférieur à celui qui a été constaté chez les résidentes ayant cumulé plus de huit heures par semaine (41,7 %) (P < 0,001). Lorsque nous avons comparé les complications obstétricales qu’ont connues les résidentes à celles qu’ont connues les femmes de la population générale, nous avons constaté que les résidentes avaient connu des taux supérieurs de fausse couche, d’hypertension pendant la grossesse, de décollement placentaire et de retard de croissance intra-utérin. Conclusion : La grossesse pendant la résidence compte un taux d’issues obstétricales indésirables plus élevé que la moyenne. Le fait de cumuler un plus grand nombre d’heures en salle d’opération et le fait d’être de garde pendant plus de six nuits par mois sont associés à des complications obstétricales. De surcroît, les résidentes enceintes sont plus susceptibles de connaître des troubles hypertensifs de la grossesse, un retard de croissance intra-utérin, un décollement placentaire et une fausse couche qu’une cohorte de femmes enceintes d’âge semblable.
Competing Interests: None declared. Received on June 16, 2014 Accepted on August 6, 2014
J Obstet Gynaecol Can 2015;36(12):25–31
JANUARY JOGC JANVIER 2015 l 25
Obstetrics
INTRODUCTION
P
regnancy can be a stressful time for any woman, but especially for a full-time working mother. Since most female residents are in their childbearing years, pregnancy often occurs during their residency training. Residents have long working hours and sometimes an unfavourable working environment.1–3 However, the effects of this workload on pregnancy outcome are still not clear. Previous studies of small cohorts have shown that pregnant residents are at increased risk for obstetrical complications such as preterm labour, preterm premature rupture of membranes, preeclampsia, low birth weight, or intrauterine fetal demise.4–8 Whether this increased risk is related to the number of working hours, time spent in the operating room, or the stress of residency training itself has not been investigated. As the number of women enrolled in residency training programs is steadily increasing, evaluation of the impact of residency training on pregnancy outcome is timely and important.3,4,9 In a study of general surgery residents in Canada , Merchant et al. found that lack of adequate policies for maternity or parenting, obstacles to breastfeeding, and the increased workload for residents made medical students planning to start a family reluctant to join the general surgery residency program.10 Many residents feel that they have no support from their program directors.4 Other studies have found that most pregnant residents have reported being treated fairly by their colleagues, and that the quality of their work has not been affected by their pregnancy.2,11 Davis et al. reviewed maternity leave policies in 274 accredited obstetrics and gynaecology residency programs in the United States; most programs agreed that maternity leave had a significant impact on the schedules of both the residents on maternity leave and the remaining residents covering their absent colleagues.12 If residency training increases the risk of pregnancy complications, and if some residency programs do not have a structured maternity leave policy, residents might postpone their childbearing. Pregnancy and childbirth during residency training may not only influence personal choices but may also affect future career planning.9,13 Because of the work and time demands of residency, residents may need to stop breastfeeding earlier than desired, and this has been shown to have a major impact on their level of satisfaction.9,13,14
ABBREVIATIONS IUGR
intrauterine growth restriction
PPROM preterm premature rupture of membranes
26 l JANUARY JOGC JANVIER 2015
The purpose of our study was to evaluate obstetrical complications of pregnancy during residency training and their possible contributing factors. METHODS
We conducted an email survey by sending a link to a webbased questionnaire (online eAppendix) to 190 surgical and medical residency programs across North America in April and May 2013. Program administrators were asked to forward the link to all female residents in their program, and the residents were encouraged to participate in the survey only if they had ever been pregnant. The questionnaire contained 10 multiple-choice questions that permitted multiple answers where applicable. The questions focused mainly on the complications that residents might have encountered during their pregnancy before and during residency training. The surveys were completed anonymously. We compared the incidence of pregnancy complications among residents to the incidence in 3767 obstetrical patients of similar age who were admitted to the Jewish General Hospital, Montreal, in the same year. We compared the proportions using chi-square test or Fisher exact test. The Institutional Review Board of the Jewish General Hospital, in Montreal, QC, provided ethics approval for the study. RESULTS
We received responses from 238 residents: 19 from medical residency programs, and 219 from surgical programs. Because of a lack of information from the programs, the overall survey response rate could not be calculated. Baseline characteristics of the responders are shown in Table 1. There were equal numbers of residents in each age group. Most residents had only one pregnancy, and 10% to 15% of residents had three or more pregnancies. All medical residents continued doing night call during pregnancy, and 10% of surgical residents were not required to do night call while pregnant. Most residents had up to six nights on call per month during their pregnancy. Residents in surgical programs (33%) tended to perform more night call than those in medical programs (10.5%). Overall, 5% to 12% of residents reported having reduced work hours while pregnant. When asked about stress while pregnant during residency, most respondents felt that their stress level was moderate.
Obstetrical Complications in Pregnant Medical and Surgical Residents
Table 1. Baseline characteristics of medical and surgical residents Medical residents
Surgical residents
(n = 19)
%
(n = 219)
%
P
25 to 29
7
36.8
78
35.6
0.9
30 to 34
9
47.4
129
58.9
0.34
35 to 40
3
15.8
11
5.0
0.11
1
12
63.2
108
49.3
0.26
2
4
21.1
61
27.9
0.55
3+
3
15.8
23
10.5
0.48
Yes
19
100
209
95.4
0.43
No
0
0
10
4.6
0.43
Age, years
Number of pregnancies*
Nights on call
Reduced working hours Yes
1
5.3
27
12.3
0.39
No
17
89.5
170
77.6
0.23
Stress Mild
0
0
10
4.6
0.43
Moderate
2
10.5
56
25.6
0.14
Severe
0
0
28
12.8
0.08
*27 surgical residents did not indicate number of pregnancies
Among surgical residents, 13% were freed from assisting at surgery while pregnant, 21% performed 16 to 23 hours per week, and 16% performed over 40 hours of surgery per week. The median duration of surgery per week was five hours (range 0 to 8). Since the average operating time per day was eight hours, we evaluated the rate of obstetrical complications among surgical residents who worked up to eight hours per week and those who worked more than eight hours per week. The rate of obstetrical complications among 56 residents who worked up to eight hours per week (8.9%) was significantly lower than among 163 residents who worked more than eight hours per week (41.7%) (OR 0.14; 95% CI 0.05 to 0.36, P < 0.001) (Figure). The rates of obstetrical complications among pregnant surgical residents and medical residents were comparable (Table 2). The number of nights on call taken by surgical residents (4, range 0 to 7) and medical residents (3, range 3 to 7) were similar. However, the rate of obstetrical complications among residents who had up to six nights on call per month (43/163, 26.4%) was significantly lower than among those who had more than six per month (37/75, 49.3%) (OR 0.37; 95% CI 0.21 to 0.65, P < 0.001) (Figure). There were no cases of intrauterine fetal death in either group of residents.
When we compared obstetrical complications among residents with those among women of similar age in the general population, we found residents had higher rates of miscarriage, hypertension in pregnancy, placental abruption, and intrauterine growth restriction (Table 3). However, the prevalence of gestational diabetes was higher in the women in the general population. DISCUSSION
Medical and surgical residents who responded to our survey were mostly (58%) aged between 30 and 34 years. Only a few residents were more than 35 years old, a category termed “advanced maternal age” with respect to obstetrical complications15 (Table 1). Although a recent release of statistics by the American Board of Emergency Medicine showed that 70% of their residents were between 27 and 32 years of age,16 another study of internal medicine residents showed that 64% were aged 20 to 30 years, but they were mostly first-year residents.17 Since our questionnaire targeted female residents who had been pregnant, the residents in our study were more likely to be older and in the later years of residency training. Most residents in both medical and surgical specialties reported having only one pregnancy, but 27% of surgical residents and 21% of medical residents had had two JANUARY JOGC JANVIER 2015 l 27
Obstetrics
Rates of obstetrical complications (%) among all residents and among surgical residents in relation to the number of nights on call per month and operating hours per week 60
50
Percent
40
30
20
10
0
Night call/month (up to 6 vs. > 6)
previous pregnancies. Some of those pregnancies might have been before residency training, and most respondents were in the age group 30 to 34 years. According to the Centers for Disease Control and Prevention Data and Statistics 2011, most births in the United States were to women in the age group 25 to 29 years.18 Several studies have shown that physicians are more likely to delay their childbearing; they are usually older at the time of first pregnancy than women in the general population.7,19 Most pregnant residents deliver during their third or fourth year of residency training.6,9 Ip et al. reported that 58% of female residents planned to have a pregnancy before completion of their training.20 However, a study evaluating surgical residents showed that more than one half of them preferred to delay childbearing until after completion of their training.21 Nevertheless, the desire to have children is high among both male and female residents. Yet most of them still postpone pregnancy. This voluntary delay may be associated with the perception of increased stress associated with pregnancy during residency training, long work hours, unpredictable work demands, and the potential for resentment on the part of fellow residents.3,4,9,22 The average number of nights on call required per month in residency is usually less than six.23,24 The median number of nights on call per month by residents in our study was three to four. However, more than one third of surgical residents still were required to be on call for seven 28 l JANUARY JOGC JANVIER 2015
Operating hours/week (up to 8 vs. > 8)
nights or more, and they experienced more obstetrical complications than those who were on call fewer nights. Surgical residency could be more demanding than medical residency in terms of working hours.25 Nevertheless, it does not seem to increase the overall rate of complications in pregnancy. We found no statistically significant difference between residents and women in the general population in the rates of PPROM, preterm labour, placental abruption, placenta previa, multiple gestations, or hospital admissions. This is in contrast to the report of Klebanoff et al., who showed increased rates of preterm labour but not preterm delivery among pregnant residents.8 Others have shown increased rates of preterm deliveries.10 However, these studies were carried out more than 20 years ago, when the stress and working hours in residency training, and the effect on pregnant residents, might have been greater.26,27 A more recent study has shown results similar to ours, with no difference in the rates of obstetrical complications.15 In our cohort of residents, compared with those in the control group, we found higher rates of IUGR (9.2% vs. 3.9%), miscarriages (11.8% vs. 4.2%), hypertensive disorders of pregnancy (10.5% vs. 6.3%), and placental abruption (1.3% vs. 0%). Previous studies have shown that residents in training are more likely to have smaller babies.6,28 Poor nutrition is a known risk factor for growth restriction in the fetus. It is possible that residents often
Obstetrical Complications in Pregnant Medical and Surgical Residents
Table 2. Comparable obstetrical complications among pregnant surgical residents and medical residents Medical residents
Surgical residents
(n = 19)
%
(n = 219)
%
P
Miscarriage
28
12.8
0
13.3
0.08
PPROM
10
4.6
0
0
0.43
Preterm labour
12
5.5
2
10.5
0.39
Placental abruption
2
0.9
1
5.2
0.23
Placenta previa
1
0.5
0
0.5
0.92
Gestational diabetes
10
4.6
2
10.5
0.31
IUGR
21
9.6
1
10.5
0.6
Hypertension
25
11.5
0
0
0.11
Twins
5
2.3
0
0
0.66
IUFD
0
0
0
0
NA
NICU admission
5
2.3
0
2.4
0.66
Hospital admission
33
15.1
1
5.2
0.26
IUFD: intrauterine fetal death; NA: not applicable.
Table 3. Obstetrical complications among residents compared with a control group of pregnant women in the general obstetrical population Residents Complications
Control women
(n = 238)
%
(n = 3767)
%
P
Miscarriage
28
11.8
157
4.2
< 0.001
PPROM
10
4.2
112
3.0
0.28
Preterm labour
14
5.9
219
5.8
0.96
Placental abruption
3
1.3
0
0
< 0.001
Placenta previa
1
0.4
78
2.1
0.09
Twins
5
2.1
77
2.0
0.81
Gestational diabetes
12
5.0
358
9.5
0.03
IUGR
22
9.2
147
3.9
< 0.001
Hypertension
25
10.5
238
6.3
0.02
Admission
34
14.3
568
15.1
0.74
have longer working hours, are more stressed, and have worse eating habits than other working women.3,4,7,9 Also, hypertensive disorders of pregnancy are associated with IUGR.29 Since residents have higher rates of hypertension in pregnancy, this could be a reason why we see higher rates of IUGR. However, in our cohort of residents the two complications were seen independently. In a 1988 study of 1197 residents in different medical specialties, Phelan reported that the rate of hypertensive disorders in pregnancy was 12% in residents and 5% in the general population.30 This finding was attributed to residents being older at the time of their first pregnancy; this might have been the case 25 years ago, but it does not explain the difference we see today. Another study of
4412 residents also showed a higher rate of preeclampsia among residents than in the spouses of male residents (8.8% vs. 3.5%).8 A smaller study had the same findings.6 It appears that residency training does increase the risk of hypertensive disorders in pregnancy. In our survey, there were more cases of placental abruption in pregnant residents than in the general population. Again, since residents had a higher rate of hypertensive disorders, this may have been an associated cause. We found significantly more cases of gestational diabetes in the general population group than in pregnant residents, even though they were of the same age. It is possible that residents are more conscious of proper nutrition and weight gain than women in the general population. JANUARY JOGC JANVIER 2015 l 29
Obstetrics
The complication rate among residents in our study was 34%. Two previous studies reported a similar rate of complications among residents (36% and 33%),7,31 while another study showed a rate as high as 57%.22 There are also some indications that physicians later in their career are also at risk for obstetrical complications.5,19 This could be related to advancing age. A large study conducted across 16 European countries showed that longer working hours in employed women increased the risk of obstetrical complications such as preterm birth,32 although the incidence of preterm labour in our cohort was similar to that in the general population.
CONCLUSION
Long working hours and prolonged standing have been associated with adverse pregnancy outcomes,32,33 and this may put pregnant residents at risk for a complicated pregnancy. Some programs offer reduced working hours for pregnant residents (restricting the working hours to a certain amount per day). Unfortunately, only 10% of the residents who had complications and 20% of the residents who had no complications reported working less when pregnant. Since long working hours might be associated with obstetrical complications, residency programs should consider offering their residents a reduction in working days and perhaps fewer nights on call when they are pregnant.
ACKNOWLEDGEMENTS
Another factor that can contribute to obstetrical complications is stress, which is common among residents. This could be attributed to many factors, including guilt over colleagues’ increased workloads, altered schedules, and unpredictable work demands.3,9 Some residents even have called their experience of being pregnant during residency training “miserable,” and would not do it again.31 Sameer et al. found a relationship between longer working hours in residency and stress among both medical and surgical residents.25 Analyzing operating hours and complications, we found that surgical residents who had to operate for more than eight hours per week were at increased risk of obstetrical complications. Performing surgery is associated with prolonged standing, prolonged concentration, and stress. Studies of work environments for pregnant women have demonstrated that prolonged standing is associated with preterm labour and other obstetrical complications.19,20 Limitations of our study include the relatively small number of medical residents who responded to our survey. In addition, it could be argued that the residents who responded to our survey were those who experienced obstetrical complications, leading to possible selection bias. 30 l JANUARY JOGC JANVIER 2015
Undertaking pregnancy during residency training increases the risk of adverse outcomes. Longer operating hours (for surgical residents) and more than six nights on call per month predispose residents to obstetrical complications. In addition, pregnant residents are more likely to have pregnancies complicated by hypertensive disorders, IUGR, placental abruption, and miscarriage than pregnant women of similar age in the general population. All residents and residency program directors should be aware of these issues.
Dr Tulandi is an advisor for Actavis Inc. Dr Behbehani has no conflict of interest. REFERENCES 1. Blake ME, Oates ME, Applegate K, Kuligowska E. Proposed program guidelines for pregnant radiology residents: a project supported by the American Association for Women Radiologists and the Association of Program Directors in Radiology. Acad Radiol 2006:391–401. 2. Carty SE, Colson YL, Garvey LS, Schuchert VD, Schwentker A, Tzeng E, et al. Maternity policy and practice during surgery residency: how we do it. Surgery 2002;132:682–7. 3. Cole S, Arnold M, Sanderson A, Cupp C. Pregnancy during otolaryngology residency: experience and recommendations. Am Surg 2009;75:411–5. 4. Finch SJ. Pregnancy during residency: a literature review. Acad Med 2003;78:418–28. 5. Hamilton AR, Tyson MD, Braga JA, Lerner LB. Childbearing and pregnancy characteristics of female orthopaedic surgeons. J Bone Joint Surg Am 2012;94:e77. 6. Gabbe SG, Morgan MA, Power ML, Schulkin J, Williams SB. Duty hours and pregnancy outcome among residents in obstetrics and gynecology. Obstet Gynecol 2003;102:948–51. 7. Pinhas-Hamiel O, Rotstein Z, Achiron A, Gabbay U, Achiron R, Barak Y, et al. Pregnancy during residency—an Israeli survey of women physicians. Health Care Women Int 1999;20:63–70. 8. Klebanoff MA, Shiono PH, Rhoads GG. Outcomes of pregnancy in a national sample of resident physicians. N Engl J Med 1990;323:1040–5. 9. Walsh A, Gold M, Jensen P, Jedrzkiewicz M. Motherhood during residency training: challenges and strategies. Can Fam Physician 2005;51:990–1. 10. Merchant SJ, Hameed SM, Melck AL. Pregnancy among residents enrolled in general surgery: a nationwide survey of attitudes and experiences. Am J Surg 2013;206:605–10. 11. Lashbrook DL, Frazier LM, Horbelt DV, Stembridge TW, Rall MJ. Pregnancy during obstetrics and gynecology residency: effect on surgical experience. Am J Obstet Gynecol 2003;189:662–5. 12. Davis JL, Baillie S, Hodgson CS, Vontver L, Platt LD. Maternity leave: existing policies in obstetrics and gynecology residency programs. Obstet Gynecol 2001;98:1093–8. 13. Hutchinson AM, Anderson NS 3rd, Gochnour GL, Stewart C. Pregnancy and childbirth during family medicine residency training. Fam Med 2011;43:160–5.
Obstetrical Complications in Pregnant Medical and Surgical Residents
14. Merchant S, Hameed M, Melck A. Pregnancy among residents enrolled in general surgery (PREGS): a survey of residents in a single Canadian training program. Can J Surg 2011;54:375–80. 15. Johnson JA, Tough S, Society of Obstetricians and Gynaecologists of Canada Genetics Committee. Delayed child-bearing. SOGC Clincial Practice Guideline no. 271, January 2012. J Obstet Gynaecol Can 2012;34(1):80–93. 16. Smith-Coggins R, Carius ML, Collier RE, Counselman FL, Kowalenko T, Marco CA, et al. Report on residency training information (2011–2012), American Board of Emergency Medicine. Ann Emerg Med 2012;59:416–24. 17. Palabindala V, Foster P, Kanduri S, Doppalapudi A, Pamarthy A, Kovvuru K. Personal health care of internal medicine residents. J Community Hosp Intern Med Perspect 2011;1:1–6. 18. Centers for Disease Control and Prevention. QuickStats: birth rates* among women aged 15–44 years, by maternal age group—national vital statistics system, United States,† 1961, 2007, and 2011§. MMWR Morb Mortal Wkly Rep 2012; 61(47);978. 19. Lerner LB, Stolzmann KL, Gulla VD. Birth trends and pregnancy complications among women urologists. J Am Coll Surg 2009;208:293–7. 20. Ip SW, Ko HS, Applegate KE. Factors influencing career choices in radiology trainees in Queensland, Australia. J Med Imaging Radiat Oncol 2010;54:93–9.
23. Tran J, Lewis R, de Virgilio C. The effect of the 80-hour work week on general surgery resident operative case volume. Am Surg 2006;72:924–8. 24. Kelly RJ Jr, Senkowski CK. Effect of the night float system on operative case volume for senior surgical residents. J Surg Educ 2009;66:314–8. 25. Sameer-ur-Rehman, Kumar R, Siddiqui N, Shahid Z, Syed S, Kadir M. Stress, job satisfaction and work hours in medical and surgical residency programmes in private sector teaching hospitals of Karachi, Pakistan. J Pak Med Assoc 2012;62:1109–12. 26. Nichols M. Curriculum change in an obstetrics-gynecology residency program and its impact on pregnancy in residency. Am J Obstet Gynecol 1994;170:1658–64; discussion 1664–5. 27. Tan P, Hogle NJ, Widmann WD. Limiting PGY 1 residents to 16 hours of duty: review and report of a workshop. J Surg Educ 2012;69:355–9. 28. Grunebaum A, Minkoff H, Blake D. Pregnancy among obstetricians: a comparison of births before, during, and after residency. Am J Obstet Gynecol 1987;157:79–83. 29. Vanek M, Sheiner E, Levy A, Mazor M. Chronic hypertension and the risk for adverse pregnancy outcome after superimposed pre-eclampsia. Int J Gynaecol Obstet 2004;86(1):7–11. 30. Phelan ST. Pregnancy during residency: II. Obstetric complications. Obstet Gynecol 1988;72:431–6. 31. Klevan JL, Weiss JC, Dabrow SM. Pregnancy during pediatric residency. Attitudes and complications. Am J Dis Child 1990;144:767–9.
21. Turner PL, Lumpkins K, Gabre J, Lin MJ, Liu X, Terrin M. Pregnancy among women surgeons: trends over time. Arch Surg 2012;147:474–9.
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JANUARY JOGC JANVIER 2015 l 31
Obstetrical Complications in Pregnant Medical and Surgical Residents Sadikah Behbehani, MD, Togas Tulandi, MD, MHCM Department of Obstetrics and Gynecology, McGill University, Montreal QC
Abstract
Résumé
Objective: Pregnant residents are at risk for obstetrical complications. The purpose of our study was to evaluate the incidence and type of obstetrical complications of pregnancy during residency training, and their possible contributing factors.
Objectif : Les résidentes enceintes sont exposées à des risques de complications obstétricales. Notre étude avait pour objectif d’évaluer l’incidence et le type des complications obstétricales constatées dans le cadre de la résidence, ainsi que leurs facteurs contributifs possibles.
Method: We conducted a retrospective cohort study using a webbased questionnaire sent to 190 residency programs, both medical and surgical, across North America. The questionnaire was distributed to all female residents, and participants were asked to answer the questionnaire only if they had ever been pregnant. The questionnaire consisted of 10 multiple-choice questions and focused mainly on the complications that residents may have encountered during pregnancy before and during their residency training. The results were compared with those of 3767 pregnant women of similar age. Results: The rate of obstetrical complications among residents who had up to six nights on call per month (43/163 or 26.4%) was significantly lower than those who had more than six nights on call per month (37/75 or 49.3%) (P < 0.001). Among surgical residents, 16% performed over 40 hours of surgery per week. The rate of obstetrical complications among residents who had up to eight hours of operating room time per week (8.9%) was significantly lower than among residents who worked more than eight hours per week (41.7%) (P < 0.001). When we compared obstetrical complications among residents with those of women in the general population, we found that residents had higher rates of miscarriage, hypertension in pregnancy, placental abruption, and intrauterine growth restriction. Conclusion: Pregnancy during residency has a higher than average rate of adverse obstetrical outcomes. Longer operating hours and having more than six nights on call per month are associated with obstetrical complications. In addition, pregnant residents are more likely to have hypertensive disorders of pregnancy, intrauterine growth restriction, placental abruption, and miscarriages than a cohort of pregnant women of similar age.
Key Words: Pregnancy complications, residency training, medical resident, surgical resident
Méthodes : Nous avons mené une étude de cohorte rétrospective au moyen d’un questionnaire Web que nous avons fait parvenir à 190 programmes de résidence, tant en médecine qu’en chirurgie, de partout en Amérique du Nord. Ce questionnaire a été distribué à toutes les résidentes et nous avons demandé aux participantes de ne remplir le questionnaire que si elles avaient déjà connu une grossesse. Le questionnaire comptait 10 questions à choix multiple et était principalement axé sur les complications de grossesse auxquelles les résidentes pourraient avoir eu à faire face avant et pendant leur résidence. Les résultats ont été comparés à ceux qui ont été obtenus par 3 767 femmes enceintes d’âge semblable. Résultats : Le taux de complications obstétricales chez les résidentes qui étaient de garde pendant jusqu’à six nuits par mois (43/163 ou 26,4 %) était considérablement inférieur à celui des résidentes qui étaient de garde pendant plus de six nuits par mois (37/75 ou 49,3 %) (P < 0,001). Parmi les résidentes en chirurgie, 16 % menaient plus de 40 heures de chirurgie par semaine. Le taux de complications obstétricales chez les résidentes qui cumulaient jusqu’à huit heures en salle d’opération par semaine (8,9 %) était considérablement inférieur à celui qui a été constaté chez les résidentes ayant cumulé plus de huit heures par semaine (41,7 %) (P < 0,001). Lorsque nous avons comparé les complications obstétricales qu’ont connues les résidentes à celles qu’ont connues les femmes de la population générale, nous avons constaté que les résidentes avaient connu des taux supérieurs de fausse couche, d’hypertension pendant la grossesse, de décollement placentaire et de retard de croissance intra-utérin. Conclusion : La grossesse pendant la résidence compte un taux d’issues obstétricales indésirables plus élevé que la moyenne. Le fait de cumuler un plus grand nombre d’heures en salle d’opération et le fait d’être de garde pendant plus de six nuits par mois sont associés à des complications obstétricales. De surcroît, les résidentes enceintes sont plus susceptibles de connaître des troubles hypertensifs de la grossesse, un retard de croissance intra-utérin, un décollement placentaire et une fausse couche qu’une cohorte de femmes enceintes d’âge semblable.
Competing Interests: None declared. Received on June 16, 2014 Accepted on August 6, 2014
J Obstet Gynaecol Can 2015;36(12):25–31
JANUARY JOGC JANVIER 2015 l 25
Obstetrics
INTRODUCTION
P
regnancy can be a stressful time for any woman, but especially for a full-time working mother. Since most female residents are in their childbearing years, pregnancy often occurs during their residency training. Residents have long working hours and sometimes an unfavourable working environment.1–3 However, the effects of this workload on pregnancy outcome are still not clear. Previous studies of small cohorts have shown that pregnant residents are at increased risk for obstetrical complications such as preterm labour, preterm premature rupture of membranes, preeclampsia, low birth weight, or intrauterine fetal demise.4–8 Whether this increased risk is related to the number of working hours, time spent in the operating room, or the stress of residency training itself has not been investigated. As the number of women enrolled in residency training programs is steadily increasing, evaluation of the impact of residency training on pregnancy outcome is timely and important.3,4,9 In a study of general surgery residents in Canada , Merchant et al. found that lack of adequate policies for maternity or parenting, obstacles to breastfeeding, and the increased workload for residents made medical students planning to start a family reluctant to join the general surgery residency program.10 Many residents feel that they have no support from their program directors.4 Other studies have found that most pregnant residents have reported being treated fairly by their colleagues, and that the quality of their work has not been affected by their pregnancy.2,11 Davis et al. reviewed maternity leave policies in 274 accredited obstetrics and gynaecology residency programs in the United States; most programs agreed that maternity leave had a significant impact on the schedules of both the residents on maternity leave and the remaining residents covering their absent colleagues.12 If residency training increases the risk of pregnancy complications, and if some residency programs do not have a structured maternity leave policy, residents might postpone their childbearing. Pregnancy and childbirth during residency training may not only influence personal choices but may also affect future career planning.9,13 Because of the work and time demands of residency, residents may need to stop breastfeeding earlier than desired, and this has been shown to have a major impact on their level of satisfaction.9,13,14
ABBREVIATIONS IUGR
intrauterine growth restriction
PPROM preterm premature rupture of membranes
26 l JANUARY JOGC JANVIER 2015
The purpose of our study was to evaluate obstetrical complications of pregnancy during residency training and their possible contributing factors. METHODS
We conducted an email survey by sending a link to a webbased questionnaire (online eAppendix) to 190 surgical and medical residency programs across North America in April and May 2013. Program administrators were asked to forward the link to all female residents in their program, and the residents were encouraged to participate in the survey only if they had ever been pregnant. The questionnaire contained 10 multiple-choice questions that permitted multiple answers where applicable. The questions focused mainly on the complications that residents might have encountered during their pregnancy before and during residency training. The surveys were completed anonymously. We compared the incidence of pregnancy complications among residents to the incidence in 3767 obstetrical patients of similar age who were admitted to the Jewish General Hospital, Montreal, in the same year. We compared the proportions using chi-square test or Fisher exact test. The Institutional Review Board of the Jewish General Hospital, in Montreal, QC, provided ethics approval for the study. RESULTS
We received responses from 238 residents: 19 from medical residency programs, and 219 from surgical programs. Because of a lack of information from the programs, the overall survey response rate could not be calculated. Baseline characteristics of the responders are shown in Table 1. There were equal numbers of residents in each age group. Most residents had only one pregnancy, and 10% to 15% of residents had three or more pregnancies. All medical residents continued doing night call during pregnancy, and 10% of surgical residents were not required to do night call while pregnant. Most residents had up to six nights on call per month during their pregnancy. Residents in surgical programs (33%) tended to perform more night call than those in medical programs (10.5%). Overall, 5% to 12% of residents reported having reduced work hours while pregnant. When asked about stress while pregnant during residency, most respondents felt that their stress level was moderate.
Obstetrical Complications in Pregnant Medical and Surgical Residents
Table 1. Baseline characteristics of medical and surgical residents Medical residents
Surgical residents
(n = 19)
%
(n = 219)
%
P
25 to 29
7
36.8
78
35.6
0.9
30 to 34
9
47.4
129
58.9
0.34
35 to 40
3
15.8
11
5.0
0.11
1
12
63.2
108
49.3
0.26
2
4
21.1
61
27.9
0.55
3+
3
15.8
23
10.5
0.48
Yes
19
100
209
95.4
0.43
No
0
0
10
4.6
0.43
Age, years
Number of pregnancies*
Nights on call
Reduced working hours Yes
1
5.3
27
12.3
0.39
No
17
89.5
170
77.6
0.23
Stress Mild
0
0
10
4.6
0.43
Moderate
2
10.5
56
25.6
0.14
Severe
0
0
28
12.8
0.08
*27 surgical residents did not indicate number of pregnancies
Among surgical residents, 13% were freed from assisting at surgery while pregnant, 21% performed 16 to 23 hours per week, and 16% performed over 40 hours of surgery per week. The median duration of surgery per week was five hours (range 0 to 8). Since the average operating time per day was eight hours, we evaluated the rate of obstetrical complications among surgical residents who worked up to eight hours per week and those who worked more than eight hours per week. The rate of obstetrical complications among 56 residents who worked up to eight hours per week (8.9%) was significantly lower than among 163 residents who worked more than eight hours per week (41.7%) (OR 0.14; 95% CI 0.05 to 0.36, P < 0.001) (Figure). The rates of obstetrical complications among pregnant surgical residents and medical residents were comparable (Table 2). The number of nights on call taken by surgical residents (4, range 0 to 7) and medical residents (3, range 3 to 7) were similar. However, the rate of obstetrical complications among residents who had up to six nights on call per month (43/163, 26.4%) was significantly lower than among those who had more than six per month (37/75, 49.3%) (OR 0.37; 95% CI 0.21 to 0.65, P < 0.001) (Figure). There were no cases of intrauterine fetal death in either group of residents.
When we compared obstetrical complications among residents with those among women of similar age in the general population, we found residents had higher rates of miscarriage, hypertension in pregnancy, placental abruption, and intrauterine growth restriction (Table 3). However, the prevalence of gestational diabetes was higher in the women in the general population. DISCUSSION
Medical and surgical residents who responded to our survey were mostly (58%) aged between 30 and 34 years. Only a few residents were more than 35 years old, a category termed “advanced maternal age” with respect to obstetrical complications15 (Table 1). Although a recent release of statistics by the American Board of Emergency Medicine showed that 70% of their residents were between 27 and 32 years of age,16 another study of internal medicine residents showed that 64% were aged 20 to 30 years, but they were mostly first-year residents.17 Since our questionnaire targeted female residents who had been pregnant, the residents in our study were more likely to be older and in the later years of residency training. Most residents in both medical and surgical specialties reported having only one pregnancy, but 27% of surgical residents and 21% of medical residents had had two JANUARY JOGC JANVIER 2015 l 27
Obstetrics
Rates of obstetrical complications (%) among all residents and among surgical residents in relation to the number of nights on call per month and operating hours per week 60
50
Percent
40
30
20
10
0
Night call/month (up to 6 vs. > 6)
previous pregnancies. Some of those pregnancies might have been before residency training, and most respondents were in the age group 30 to 34 years. According to the Centers for Disease Control and Prevention Data and Statistics 2011, most births in the United States were to women in the age group 25 to 29 years.18 Several studies have shown that physicians are more likely to delay their childbearing; they are usually older at the time of first pregnancy than women in the general population.7,19 Most pregnant residents deliver during their third or fourth year of residency training.6,9 Ip et al. reported that 58% of female residents planned to have a pregnancy before completion of their training.20 However, a study evaluating surgical residents showed that more than one half of them preferred to delay childbearing until after completion of their training.21 Nevertheless, the desire to have children is high among both male and female residents. Yet most of them still postpone pregnancy. This voluntary delay may be associated with the perception of increased stress associated with pregnancy during residency training, long work hours, unpredictable work demands, and the potential for resentment on the part of fellow residents.3,4,9,22 The average number of nights on call required per month in residency is usually less than six.23,24 The median number of nights on call per month by residents in our study was three to four. However, more than one third of surgical residents still were required to be on call for seven 28 l JANUARY JOGC JANVIER 2015
Operating hours/week (up to 8 vs. > 8)
nights or more, and they experienced more obstetrical complications than those who were on call fewer nights. Surgical residency could be more demanding than medical residency in terms of working hours.25 Nevertheless, it does not seem to increase the overall rate of complications in pregnancy. We found no statistically significant difference between residents and women in the general population in the rates of PPROM, preterm labour, placental abruption, placenta previa, multiple gestations, or hospital admissions. This is in contrast to the report of Klebanoff et al., who showed increased rates of preterm labour but not preterm delivery among pregnant residents.8 Others have shown increased rates of preterm deliveries.10 However, these studies were carried out more than 20 years ago, when the stress and working hours in residency training, and the effect on pregnant residents, might have been greater.26,27 A more recent study has shown results similar to ours, with no difference in the rates of obstetrical complications.15 In our cohort of residents, compared with those in the control group, we found higher rates of IUGR (9.2% vs. 3.9%), miscarriages (11.8% vs. 4.2%), hypertensive disorders of pregnancy (10.5% vs. 6.3%), and placental abruption (1.3% vs. 0%). Previous studies have shown that residents in training are more likely to have smaller babies.6,28 Poor nutrition is a known risk factor for growth restriction in the fetus. It is possible that residents often
Obstetrical Complications in Pregnant Medical and Surgical Residents
Table 2. Comparable obstetrical complications among pregnant surgical residents and medical residents Medical residents
Surgical residents
(n = 19)
%
(n = 219)
%
P
Miscarriage
28
12.8
0
13.3
0.08
PPROM
10
4.6
0
0
0.43
Preterm labour
12
5.5
2
10.5
0.39
Placental abruption
2
0.9
1
5.2
0.23
Placenta previa
1
0.5
0
0.5
0.92
Gestational diabetes
10
4.6
2
10.5
0.31
IUGR
21
9.6
1
10.5
0.6
Hypertension
25
11.5
0
0
0.11
Twins
5
2.3
0
0
0.66
IUFD
0
0
0
0
NA
NICU admission
5
2.3
0
2.4
0.66
Hospital admission
33
15.1
1
5.2
0.26
IUFD: intrauterine fetal death; NA: not applicable.
Table 3. Obstetrical complications among residents compared with a control group of pregnant women in the general obstetrical population Residents Complications
Control women
(n = 238)
%
(n = 3767)
%
P
Miscarriage
28
11.8
157
4.2
< 0.001
PPROM
10
4.2
112
3.0
0.28
Preterm labour
14
5.9
219
5.8
0.96
Placental abruption
3
1.3
0
0
< 0.001
Placenta previa
1
0.4
78
2.1
0.09
Twins
5
2.1
77
2.0
0.81
Gestational diabetes
12
5.0
358
9.5
0.03
IUGR
22
9.2
147
3.9
< 0.001
Hypertension
25
10.5
238
6.3
0.02
Admission
34
14.3
568
15.1
0.74
have longer working hours, are more stressed, and have worse eating habits than other working women.3,4,7,9 Also, hypertensive disorders of pregnancy are associated with IUGR.29 Since residents have higher rates of hypertension in pregnancy, this could be a reason why we see higher rates of IUGR. However, in our cohort of residents the two complications were seen independently. In a 1988 study of 1197 residents in different medical specialties, Phelan reported that the rate of hypertensive disorders in pregnancy was 12% in residents and 5% in the general population.30 This finding was attributed to residents being older at the time of their first pregnancy; this might have been the case 25 years ago, but it does not explain the difference we see today. Another study of
4412 residents also showed a higher rate of preeclampsia among residents than in the spouses of male residents (8.8% vs. 3.5%).8 A smaller study had the same findings.6 It appears that residency training does increase the risk of hypertensive disorders in pregnancy. In our survey, there were more cases of placental abruption in pregnant residents than in the general population. Again, since residents had a higher rate of hypertensive disorders, this may have been an associated cause. We found significantly more cases of gestational diabetes in the general population group than in pregnant residents, even though they were of the same age. It is possible that residents are more conscious of proper nutrition and weight gain than women in the general population. JANUARY JOGC JANVIER 2015 l 29
Obstetrics
The complication rate among residents in our study was 34%. Two previous studies reported a similar rate of complications among residents (36% and 33%),7,31 while another study showed a rate as high as 57%.22 There are also some indications that physicians later in their career are also at risk for obstetrical complications.5,19 This could be related to advancing age. A large study conducted across 16 European countries showed that longer working hours in employed women increased the risk of obstetrical complications such as preterm birth,32 although the incidence of preterm labour in our cohort was similar to that in the general population.
CONCLUSION
Long working hours and prolonged standing have been associated with adverse pregnancy outcomes,32,33 and this may put pregnant residents at risk for a complicated pregnancy. Some programs offer reduced working hours for pregnant residents (restricting the working hours to a certain amount per day). Unfortunately, only 10% of the residents who had complications and 20% of the residents who had no complications reported working less when pregnant. Since long working hours might be associated with obstetrical complications, residency programs should consider offering their residents a reduction in working days and perhaps fewer nights on call when they are pregnant.
ACKNOWLEDGEMENTS
Another factor that can contribute to obstetrical complications is stress, which is common among residents. This could be attributed to many factors, including guilt over colleagues’ increased workloads, altered schedules, and unpredictable work demands.3,9 Some residents even have called their experience of being pregnant during residency training “miserable,” and would not do it again.31 Sameer et al. found a relationship between longer working hours in residency and stress among both medical and surgical residents.25 Analyzing operating hours and complications, we found that surgical residents who had to operate for more than eight hours per week were at increased risk of obstetrical complications. Performing surgery is associated with prolonged standing, prolonged concentration, and stress. Studies of work environments for pregnant women have demonstrated that prolonged standing is associated with preterm labour and other obstetrical complications.19,20 Limitations of our study include the relatively small number of medical residents who responded to our survey. In addition, it could be argued that the residents who responded to our survey were those who experienced obstetrical complications, leading to possible selection bias. 30 l JANUARY JOGC JANVIER 2015
Undertaking pregnancy during residency training increases the risk of adverse outcomes. Longer operating hours (for surgical residents) and more than six nights on call per month predispose residents to obstetrical complications. In addition, pregnant residents are more likely to have pregnancies complicated by hypertensive disorders, IUGR, placental abruption, and miscarriage than pregnant women of similar age in the general population. All residents and residency program directors should be aware of these issues.
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