Pregnancy increases stroke risk up to 1 year postpartum and reduces long-term risk

Background: The incidence of stroke in pregnant women is low but trending upward. There are few studies of the topic in women of Asian ethnicity. Aim: We aim to evaluate stroke risk in Asian women during and after pregnancy. Design: Using the Taiwan National Health Insurance database, we designed a retrospective study that included 18-45-yearold pregnant women between the years 2000 and 2010. We selected a 1:1 age-matched control group of non-pregnant women. The endpoint was any type of stroke during pregnancy or the postpartumperiod; otherwise, the patients were tracked until 31 December 2010. Methods: The risk factors for stroke were found using Cox proportional regression to calculate the hazard ratio (HR) with a 95% CI compared with the control group. Results: The incidence of stroke within 1 year postpartumwas 71/100,000. The risk of postpartum stroke within 1 year was an HR of 1.208 (95% CI: 1.001-5.129). The occurrence of stroke was associated with hypertension, diabetes mellitus, coagulation disorders, migraine, obesity, cerebrovascular malformation and parity. Women with third and fourth parity carried increased risks of 13.3% and 2.5%, respectively, compared with first parity women. In long-term follow-ups, stroke risk was significantly lower, with an adjusted HR of 0.362 (95% CI: 0.269-0.489). Conclusion: The risk of stroke was elevated during the first year postpartum, but lower in subsequent years. Stroke risk increased in multiparous (≥ 3) women. Physicians should be on alert for pregnancy complications and ensure appropriate management to prevent postpartum stroke.