To determine trends in anti-epileptic drug (AED) use and malformation rate over two decades in the Kerala registry of Epilepsy and Pregnancy (KREP).

This registry had been prospectively following up pregnancies in women with epilepsy and screening for MCM since 1998. In the present study, AED usage and the MCM rate for all completed pregnancies with a known outcome enrolled in this registry between 1998 and 2018 were analysed. Changes in usage of AEDs and MCM rate were analysed in blocks of five years.

2389 pregnancies were included in the study. Overall MCM rate was 5.8% (N=139). Change in use of AEDs from block 1 to block 4 was significant (p<0.001) for: phenobarbitone (39% to 5.9%), phenytoin (40.2% to 4.7%), valproate (27% to 10.6%), oxcarbazepine (0.7% to 25.5%), levetiracetam (0 to 45.6%) and clobazam (6.3% to 29.3%). Other AEDs such as lamotrigine (12.1% to 17.2%) and topiramate (8.3% to 22.2%) showed increasing trend, though number of exposures was limited to ascertain statistical significance. The overall MCM rates over two decades had reduced from 28.1% to 10.8%, though it was not statistically significant.