A Hospital-Based Cross-Sectional Study Assessing the Relation between Time of Birth and Perinatal Outcome

Objectives: Investigating the relation between perinatal outcomes and hospital working shifts. Methods: We conducted a cross-sectional study at Philippe Maguilen Senghor health center (PMSHC) in Dakar, Senegal from January, 1st 2011 to December, 31th 2018. The study population was comprised of all mothers who had delivered at PMSHC and their newborns after completing 22 weeks of gestation. Time of delivery was divided into three periods of working hours: morning shift (deliveries occurred between 7 am and 4:59 pm); evening shift from 5 pm to 10:59 pm and night shift from 11 pm to 6:59 am. Maternal outcomes were assessed by mode of delivery, epsisotomy and perineal injuries. The Apgar scoring system was used to assess newborns at first minute after they were born. Other adverse perinatal outcomes included fresh stillbirth, neonatal referral and early neonatal death. Data were analyzed using Statistical Package for Social Science software (SPSS 24, Mac version). Results: A total of 48,270 mothers and their newborns met eligibility criteria. Caesarean section deliveries were less likely to occur during evening (OR 0.84, 95% CI; 0.79 - 0.89, p = 0.001) and night shifts (OR 0.45, CI; 0.47 - 0.53, p = 0.001). Evening shift deliveries had 1.1 the odds of poor perinatal outcome (Apgar score  - 1.18, p = 0.012). No significant difference was found in the odds of neonate referrals and deaths across the three shifts. Night shift deliveries had 1.1 the odds of perineal injuries compared to morning shift deliveries (OR 1.11, 95% CI; 1.04 - 1.18, p = 0.001, for episiotomy and OR, 1.14; 95% CI, 1.04 - 1.26, p = 0.008, for perineal tears). Conclusion: Off-hours deliveries, particularly during the night shift, were significantly associated with higher proportions of perineal injuries compared to morning shift. However, no significant difference was found in the odds of neonate referrals and deaths across the three shifts. Our findings suggest to set up a Neonatology unit at the CSPMS as well as a perinatal network across the country.