Maternal and obstetric factors associated with delayed postpartum eclampsia: a national study population

Objective: To estimate the incidence of delayed postpartum eclampsia and to investigate whether maternal characteristics and outcomes were different between women with delayed or early postpartum eclampsia.

Design: Prospective population-based study.

Setting: All 229 UK hospitals with consultant-led maternity units in the UK.

Population: All women delivering between February 2005 and February 2006.

Methods: Maternal characteristics and outcomes were compared between women with delayed (≥ 12 hours between delivery and eclampsia) and early postpartum eclampsia.

Main outcome measures: Rates with 95% confidence intervals (CIs). Adjusted odds ratio estimates.

Results: Seventy-six women had postpartum eclampsia, representing an incidence of 1.0/10 000 (95% CI 0.7-1.2/10 000) maternities. Among the women having postpartum eclampsia, 53 (70%; 95% CI 59-79) occurred in the first 12 hours following delivery, eight (11%; 95% CI 3-20) during hours 12-24, four (5%; 95% CI 2-13) during the 24-48 hours after delivery and 11 (14%; 95% CI 7-24) more than 48 hours after delivery. Maternal characteristics, biological and clinical symptoms in the week preceding eclampsia and neonatal outcomes were not significantly different in the delayed eclampsia group in comparison with the early postpartum eclampsia group. However, the cesarean delivery rate was higher in women with delayed eclampsia in comparison with earlier postpartum eclampsia [13 (57%) vs. 6 (11%); odds ratio 10.1, 95% CI 3.12-33.3].

Conclusions: Close follow-up should be performed in the 12 hours following delivery in women with hypertensive disorders of pregnancy. Beyond this, the risk of eclampsia is very low, and eclampsia occurs mainly among women who have had a cesarean delivery.