Characterization of pregnancies among women with epilepsy using valproate before or during pregnancy - A longitudinal...

To characterize pregnancies among women with epilepsy who have filled a prescription for valproate at any time before or during pregnancy and to assess other antiepileptic drug (AED) prescriptions.

Based on health claims data (German Pharmacoepidemiological Research Database - GePaRD; covering ~20% of the population), we selected pregnancies beginning between 2014 and 2016 in women with at least three years of observation period before pregnancy and with at least one epilepsy diagnosis code in the year before pregnancy. Among those, we selected pregnancies with at least one valproate dispensation any time before or during pregnancy. We further described these pregnancies regarding patterns in the dispensation of valproate and other AED among the women from their first day in the database until the end of the pregnancy.

Among 2068 pregnancies fulfilling the inclusion criteria, we identified 454 pregnancies (89% ending in live births and 8% in induced abortions) in 430 women with at least one valproate dispensation before or during pregnancy. In 357 of these pregnancies (79%), valproate was only dispensed before pregnancy, while 97 pregnancies (21%) had a valproate dispensation during pregnancy and of these, 77% (N = 75) during the first trimester. The proportion with a valproate dispensation during pregnancy declined from 2014 (25%) to 2016 (19%), also concerning exposure during the first trimester (2014: 20%, 2015: 17%, 2016: 12%), while the proportion ending in an induced abortion was increasing (2014: 5%, 2015: 8%, 2016: 13%). In 48% of exposed pregnancies (N = 36), there was no other AED dispensed during the entire observation time before pregnancy. This proportion was lower for pregnancies beginning in 2016 (33%) than for those beginning in 2014 and 2015 (53% and 50%, respectively).

In most women with epilepsy using valproate before or during pregnancy, valproate was dispensed only well before pregnancy beginning. The proportion exposed to valproate during the first trimester declined between 2014 and 2016, but the low proportion treated with alternative AED before valproate treatment suggests there is still room for improvement.