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Published on: November 20, 2015
Does Time of Delivery Influence the Risk of Neonatal Morbidity?
Kathleen F Brookfield1, Katharine O'Malley1, Yasser Y El-Sayed1
1Department of Obstetrics and Gynecology, Stanford University School of Medicine, Stanford, California.
Objective:
To examine whether time of delivery influences the risk of neonatal morbidity among women with singleton pregnancies.
Study Design:
Secondary analysis of data from the Maternal Fetal Medicine Units Network Factor V Leiden Mutation study. We categorized time of delivery as day (07:00-16:59), evening (17:00-23:59), and overnight (midnight-06:59). Severe neonatal morbidity was defined by at least one of the following: respiratory distress syndrome, transient tachypnea of the newborn, sepsis, seizures, neonatal intensive care admission, or a 5-minute APGAR ≤3. We calculated frequencies of severe neonatal morbidity by time of delivery. Multivariate analysis was performed to determine whether time of delivery was independently associated with severe neonatal morbidity.
Results:
Among 4,087 women, 1,917 (46.9%) delivered during the day, 1,140 (27.9%) delivered in the evening, and 1,030 (25.2%) delivered overnight. We observed no significant differences in the rates of neonatal morbidity between delivery time periods (day: 12.3%; evening: 12.8%; overnight: 12.6%; p = 0.9). No significant association was observed between time of delivery and neonatal morbidity after adjustment for maternal, obstetric, and peripartum factors.
Conclusion:
Our findings suggest that time of delivery is not associated with severe neonatal morbidity.
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