Women treated for epilepsy during pregnancy: outcomes from a nationwide population-based cohort study

Introduction. Women with epilepsy (WWE) are generally treated as a risk group during pregnancy, but over 90% of pregnant WWE have favorable pregnancies. However, the risk of some pregnancy and delivery complications may be increased among WWE, especially those on antiepileptic drugs. Material and methods. This nationwide, retrospective population-based cohort study includes WWE who gave birth in Finland during 1987-2008 (n = 1737) and the reference cohort of a random sample of women without epilepsy (n = 4357). Identification of the cohorts, and information on hospitalizations and deliveries were obtained from the Finnish Health Registers and population statistics. Multivariate analyses were conducted by binomial regression. Results. WWE were more often hospitalized during pregnancy for accidents or other external causes [ adjusted risk ratio (aRR) 1.74, 95% confidence interval (CI) 0.98-3.09], premature rupture of membranes (aRR 1.75, 95% CI 1.14-2.69) and premature contractions (aRR 1.75, 95% CI 1.36-2.23). Hospitalizations for infections were more frequent in WWE (1.4% vs. 0.4%, aRR 3.15, 95% CI 1.72-5.76). The risk for induction of delivery or a cesarean section was increased in WWE. There was no difference in premature deliveries between the groups, but the risk of being small for gestational age (aRR 1.57, 95% CI 1.23-2.01), admission to neonatal intensive care unit (aRR 1.66, 95% CI 1.39-1.97), and need for respiratory care (aRR 2.37, 95% CI 1.57-3.60) was clearly increased in the offspring of WWE. Conclusions. WWE are at an increased risk of complications and hospitalizations during pregnancy and delivery. However, the majority of WWE have a normal pregnancy and delivery.