Delivery outcome of women with epilepsy:a population-based cohort study

Objective To investigate whether women with epilepsy have increased risks of complications during labour, and to explore the impact of antiepileptic drug use. Design Population-based cohort study. Setting Data from the Medical Birth Registry of Norway 1999-2005. Population All births (n = 372 128) delivered in Norway, ensured through linkage with the National Population Registry run by Statistics Norway. All singleton births and the first child in multiple pregnancies were included, leaving 365 107 pregnancies for analysis. Methods Data from the Medical Birth Registry of Norway 1999-2005 were analysed. Main outcome measures Induction, caesarean section, use of forceps and vacuum, abnormal presentation, placental abruption, mechanical disproportion, postpartum haemorrhage, atony and Apgar score < 7 after 5 minutes. Results We compared 2805 pregnancies in women with a current or past history of epilepsy (0.8%) and 362 302 pregnancies in women without a history of epilepsy. Antiepileptic drugs were used in 33.6% (n = 942) of pregnant women with epilepsy. Women with epilepsy had an increased risk of induction [odds ratio (OR), 1.3; 95% confidence interval (CI), 1.1-1.4], caesarean section (OR, 1.4; 95% CI, 1.3-1.6) and postpartum haemorrhage (OR, 1.2; 95% CI, 1.1-1.4) compared with women without epilepsy. These rates were even higher for women with epilepsy and antiepileptic drug use, with ORs (95% CIs) of 1.6 (1.4-1.9), 1.6 (1.4-1.9) and 1.5 (1.3-1.9), respectively. In addition, the risk of an Apgar score < 7 was higher (OR, 1.6; 95% CI, 1.1-2.4). For women with epilepsy without antiepileptic drug use, only a slightly increased risk of caesarean delivery was observed and no increased risk for any other complications studied. Conclusions Pregnant women with epilepsy have a low complication rate; however, they have a slightly increased risk of induction, caesarean section and postpartum haemorrhage. It is not possible to ascertain on the basis of this study whether this is a result of more severe epilepsy or antiepileptic drug use.