Increased adverse perinatal outcome of hospital delivery at night

BJOG. 2010 Aug;117(9):1098-107. doi: 10.1111/j.1471-0528.2010.02611.x. Epub 2010 May 25.


Objective: To determine whether delivery in the evening or at night and some organisational features of maternity units are related to perinatal adverse outcome.

Design: A 7-year national registry-based cohort study.

Setting: All 99 Dutch hospitals.

Population: From nontertiary hospitals (n = 88), 655 961 singleton deliveries from 32 gestational weeks onwards, and, from tertiary centres (n = 10), 108 445 singleton deliveries from 22 gestational weeks onwards.

Methods: Multiple logistic regression analysis of national perinatal registration data over the period 2000-2006. In addition, multilevel analysis was applied to investigate whether the effects of time of delivery and other variables systematically vary across different hospitals.

Main outcome measures: Delivery-related perinatal mortality (intrapartum or early neonatal mortality) and combined delivery-related perinatal adverse outcome (any of the following: intrapartum or early neonatal mortality, 5-minute Apgar score below 7, or admission to neonatal intensive care).

Results: After case mix adjustment, relative to daytime, increased perinatal mortality was found in nontertiary hospitals during the evening (OR, 1.32; 95% CI, 1.15-1.52) and at night (OR, 1.47; 95% CI, 1.28-1.69) and, in tertiary centres, at night only (OR, 1.20; 95% CI, 1.06-1.37). Similar significant effects were observed using the combined perinatal adverse outcome measure. Multilevel analysis was unsuccessful; extending the initial analysis with nominal hospital effects and hospital-delivery time interaction effects confirmed the significant effect of night in nontertiary hospitals, whereas other organisational effects (nontertiary, tertiary) were taken up by the hospital terms.

Conclusion: Hospital deliveries at night are associated with increased perinatal mortality and adverse perinatal outcome. The time of delivery and other organisational features representing experience (seniority of staff, volume) explain hospital-to-hospital variation.

Publication types

  • Multicenter Study

MeSH terms

  • Adult
  • Clinical Competence / standards
  • Cohort Studies
  • Delivery, Obstetric / mortality
  • Delivery, Obstetric / statistics & numerical data*
  • Female
  • Gestational Age
  • Health Facility Size / statistics & numerical data
  • Hospitalization / statistics & numerical data
  • Hospitals, Maternity / statistics & numerical data
  • Humans
  • Maternal Age
  • Medical Staff, Hospital / standards
  • Netherlands / epidemiology
  • Parity
  • Perinatal Mortality
  • Pregnancy
  • Pregnancy Outcome / epidemiology*
  • Regression Analysis
  • Time Factors
  • Young Adult