Background Prevalence of migraine is high during the reproductive age. Although migraine often improves during pregnancy, the risk of adverse pregnancy, birth, neonatal, and neurological outcomes in mother and offspring remains poorly understood. Objective To investigate the associations between maternal migraine and risks of adverse pregnancy outcomes in the mother, and birth, neonatal and postnatal outcomes in the offspring. Methods We used Danish population registries to assemble a cohort of pregnancies among women with migraine and an age‐ and conception year‐matched comparison cohort of pregnancies among women without migraine. The study period was 2005‐2012. We computed adjusted prevalence ratios (aPRs) for pregnancy and birth outcomes and adjusted risk ratios (aRRs) for neonatal and postnatal outcomes, adjusting for age, preconception medical history, and preconception reproductive history. Results We identified 22,841 pregnancies among women with migraine and 228,324 matched pregnancies among women without migraine. Migraine was associated with an increased risk of pregnancy‐associated hypertension disorders (aPR: 1.50 [95% confidence interval (CI): 1.39‐1.61]) and miscarriage (aPR: 1.10 [95% CI: 1.05‐1.15]). Migraine was associated with an increased prevalence of low birth weight (aPR: 1.14 [95% CI: 1.06‐1.23]), preterm birth (aPR: 1.21 [95% CI: 1.13‐1.30]) and cesarean delivery (aPR: 1.20 [95% CI: 1.15‐1.25]), but not of small for gestational age offspring (aPR: 0.94 [95% CI: 0.88‐0.99]) and birth defects (aPR: 1.01 [95% CI: 0.93‐1.09]). Offspring prenatally exposed to maternal migraine had elevated risks of several outcomes in the neonatal and postnatal period, including intensive care unit admission (aRR: 1.22 [95% CI: 1.03‐1.45]), hospitalization (aRR: 1.12 [95% CI: 1.06‐1.18]), dispensed prescriptions (aRR: 1.34 [95% CI: 1.24‐1.45]), respiratory distress syndrome (aRR: 1.20 [95% CI: 1.02‐1.42]), and febrile seizures (aRR: 1.27 [95% CI: 1.03‐1.57), but not of death (aRR: 0.67 [95% CI: 0.43‐1.04]) and cerebral palsy (aRR: 1.00 [95% CI: 0.51‐1.94]). Conclusions Women with migraine and their offspring have greater risks of several adverse pregnancy outcomes than women without migraine.

Background and Objectives:To examine risks of stroke recurrence and mortality after first and recurrent stroke.Methods:Using Danish nationwide health registries, we included patients (age ≥18 years) with first-time ischemic stroke (N = 105,397) or intracerebral hemorrhage (N = 13,350) during 2004–2018. Accounting for the competing risk of death, absolute risks of stroke recurrence were computed separately for each stroke subtype and within strata of age groups, sex, stroke severity, body mass index, smoking, alcohol, the Essen stroke risk score, and atrial fibrillation. Mortality risks were computed after first and recurrent stroke.Results:After adjusting for competing risks, the overall 1-year and 10-year risks of recurrence were 4% and 13% following first-time ischemic stroke and 3% and 12% following first-time intracerebral hemorrhage. For ischemic stroke, the risk of recurrence increased with age, was higher for men and following mild than more severe stroke. The most marked differences were across Essen risk scores, for which recurrence risks increased with increasing scores. For intracerebral hemorrhage, risks were similar for both sexes and did not increase with Essen risk score. For ischemic stroke, the 1-year and 10-year risks of all-cause mortality were 17% and 56% after a first-time stroke and 25% and 70% after a recurrent stroke; corresponding estimates for intracerebral hemorrhage were 37% and 70% after a first-time event and 31% and 75% after a recurrent event.Conclusion:The risk of stroke recurrence was substantial following both subtypes, but risks differed markedly among patient subgroups. The risk of mortality was higher after a recurrent than first-time stroke.