(B-096) Utilization of migraine treatments in pregnancy: results of a regulator-mandated population-based study in four Nordic countries (EUPAS36014)

Background: Migraine, a leading contributor to the burden of disease, is particularly prevalent among people of reproductive age. Although calcitonin gene-related peptide (CGRP) antibodies are approved for the prevention of migraine, their use may be limited in pregnancy due to lack of reproductive safety data.

Objectives: This study presents results of two exploratory objectives of a drug utilization study EUPAS36014: to describe utilization of erenumab and other preventive migraine medications in pregnancy and to estimate prevalences of adverse pregnancy outcomes (hypertensive disorders, gestational diabetes, cesarean delivery) and birth complications (preterm birth and small for gestational age, SGA) among pregnant persons with migraine according to migraine treatment received.

Methods: This was a prevalence study based on on data from population-based registries in Denmark, Finland, Norway, and Sweden. The study population included pregnancies in people with migraine and their offspring, identified in medical birth registries between August 2018 and September 2022. The treatment groups, defined hierarchically, were: erenumab, other CGRP antibodies, botulinum toxin, other preventive migraine medications, acute migraine medications only, and untreated migraine. We estimated prevalences of pregnancy complications in pregnancies and prevalences of birth outcomes in liveborn offspring All analyses were descriptive.

Results: There were 208 pregnancies and 209 infants exposed to erenumab between 90 days preconception and pregnancy end: 44 (Finland), 98 (Norway), and 66 (Sweden). Fewer than 5 pregnancies were exposed to erenumab in Denmark. The numbers of pregnancies in the other treatment groups were 82 for other CGRP antibodies, 653 for botulinum toxin, 5372 for other preventive migraine medications, 13246 for acute migraine medications only, and 25637 for untreated migraine. The prevalences in erenumab-treated and untreated-migraine pregnancies were 6.7% and 6.5% for pregnancy hypertensive disorders, 6.3% and 7.8% for gestational diabetes, and 23.6% and 19.0% for cesarean delivery. The mean gestational age was 39.2 and 39.3 weeks, and prevalences of SGA were 5.7% and 6.7% for erenumab-treated and untreated migraine.

Conclusions: In the four years following emergence of novel prophylactic migraine treatments, close to 300 pregnancies were exposed to CGRP antibodies in Denmark, Norway, Finland, and Sweden. These results inform future studies of the reproductive safety of novel prophylactic migraine medications. Availability of large population-based databases is important for reliable inferences from such studies.