Intrapartum and neonatal mortality in primary midwife-led and secondary obstetrician-led care in the Amsterdam region of the Netherlands: a retrospective cohort study

Abstract

To compare intrapartum- and neonatal mortality and intervention rates in term women starting labour in primary midwife-led versus secondary obstetrician-led care.Retrospective cohort study.Amsterdam region of the Netherlands.Women with singleton pregnancies who gave birth beyond 37+0 weeks gestation in the years 2005 up to 2008 and lived in the catchment area of the neonatal intensive care units of both academic hospitals in Amsterdam. Women with a primary caesarean section or a pregnancy complicated by antepartum death or major congenital anomalies were excluded. For women in the midwife-led care group, a home or hospital birth could be planned.Analysis of linked data from the national perinatal register, and hospital- and midwifery record data. We assessed (unadjusted) relative risks with confidence intervals. Main outcome measures were incidences of intrapartum and neonatal (<28 days) mortality. Secondary outcomes included incidences of caesarean section and vaginal instrumental delivery.53,123 women started labour in primary care and 30,166 women in secondary care. Intrapartum and neonatal mortality rates were 37/53,123 (0.70‰) in the primary care group and 24/30,166 (0.80‰) in the secondary care group (relative risk 0.88; 95% CI 0.52-1.46). Women in the primary care group were less likely to deliver by secondary caesarean section (5% versus 16%; RR 0.31; 95% CI 0.30-0.32) or by instrumental delivery (10% versus 13%; RR 0.76; 95% CI 0.73-0.79).We found a low absolute risk of intrapartum and neonatal mortality, with a comparable risk for women who started labour in primary versus secondary care. The intervention rate was significantly lower in women who started labour in primary care.These findings suggest that it is possible to identify a group of women at low risk of complications that can start labour in primary care and have low rates of medical interventions whereas perinatal mortality is low.