The use of enzyme-inducing anticonvulsant drugs (ACDs) in late pregnancy does not increase the risk for bleeding complications significantly, including postpartum hemorrhage (PPH) and neonatal bleeding complications, according to results of a population-based cohort study published in Neurology.
The enzyme-inducing ACDs evaluated included carbamazepine, phenobarbital, phenytoin, oxcarbazepine, and topiramate. Relative risks (RRs) and 95% CIs of PPH and neonatal bleeding complications were estimated.
Of 11,572 women with an ACD prescription that overlapped delivery, 2.6% (135 of 5109) of those in the enzyme-inducing ACD group and 3.6% (231 of 6463) of those in the other ACD group had a diagnosis of PPH (unadjusted RR 0.74; 95% CI, 0.60-0.91; adjusted RR 0.77; 95% CI, 0.58-1.00).
Neonatal bleeding complications were reported in 3.1% (157 of 5109) of those in the enzyme-inducing ACD arm vs 3.5% (229 of 6463) of those in the other ACD arm (unadjusted RR 0.87; 95% CI, 0.71-1.06; adjusted RR 0.83; 95% CI, 0.64-1.08).
The investigators concluded that the evidence from this large study implies that the use of enzyme-inducing ACDs close to delivery is not linked with an elevated risk for bleeding complications compared with the use of other ACDs in settings in which vitamin K is a standard of care among pregnant women. The findings of the current study offer some reassurance with respect to hemorrhagic complications for clinicians and for pregnant women who are successfully treated with enzyme-inducing ACDs.
Panchaud A, Cohen JM, Patorno E, et al. Anticonvulsants and the risk of perinatal bleeding complications: a pregnancy cohort study. Neurology. 2018;91:e533-e542.