Migraine and risk of hypertensive disorders of pregnancy: A population-based cohort study.

BACKGROUND: Migraine is associated with hypertensive disorders of pregnancy through common pathophysiological features. This study evaluates the association between migraine diagnosis and treatment, and risk of hypertensive disorders of pregnancy. METHODS: We conducted a prospective cohort study in the Clinical Practice Research Datalink GOLD, a large longitudinal database of patient records in the UK. We analyzed data from liveborn or stillborn singleton deliveries from 1993-2020 with at least 24 months of medical history and no history of cardiovascular disease (n = 1,049,839). We ascertained migraine through diagnosis or prescription codes before 20 weeks of gestation and hypertensive disorders of pregnancy through diagnosis codes between 20 weeks of pregnancy and delivery. We used log-binomial regression models to estimate the risk ratio and 95% confidence intervals, comparing risk of hypertensive disorders of pregnancy among individuals with migraine to those without migraine, adjusting for confounders. CONCLUSIONS: A history of migraine prior to pregnancy was associated with an increased risk of hypertensive disorders of pregnancy (RR = 1.17, 95% CI: 1.09-1.26). The greatest risk was among those with pre-pregnancy migraine that persisted into the first trimester (RR = 1.84, 95% CI: 1.35-2.50). Use of migraine medication was associated with a higher risk of hypertensive disorders of pregnancy compared to non-migraineurs (RR = 1.50, 95% CI: 1.15-1.97). Results from this study indicate that migraine is a potential risk factor for hypertensive disorders of pregnancy.