Background: Migraine, a common chronic-intermittent disorder of idiopathic origin characterized by severe debilitating headaches and autonomic nervous system dysfunction, and preeclampsia, a hypertensive disorder of pregnancy, share many common epidemiological and pathophysiological characteristics. Both conditions are associated with higher subsequent risk of ischemic stroke. Moreover, endothelial dysfunction, platelet activation, hyper-coagulation, and inflammation are common to both disorders. We assessed the risk for preeclampsia in relation to the maternal history of migraine before and during pregnancy in Peruvian women. Methods: Cases consisted of 339 women with preeclampsia, and controls were 337 normotensive women. During in-person interviews conducted at delivery, women were asked whether they had physician-diagnosed migraines, and they were asked questions that allowed for headaches and migraines to be classified according to criteria established by the International Headache Society (IHS). Logistic regression procedures were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Results: A history of any headache before or during pregnancy was associated with a 2.4-fold increased risk for preeclampsia (OR = 2.4; 95% CI 1.7-3.3). Women classified as having migraines that began prior to pregnancy had a 3.5-fold increased risk for preeclampsia (95% CI 1.9-6.4) as compared with those who reported no migraines. Women with migraines during pregnancy had a fourfold increased risk of preeclampsia (OR = 4.0, 95% CI 1.9-8.2) compared with non-migraineurs. Conclusion: sOur findings are consistent with previous reports and we have extended them to the Peruvian population. Prospective cohort studies, however, are needed to more rigorously evaluate the extent to which migraines and/or its treatments are associated with the occurrence of preeclampsia. © 2008 American Journal of Hypertension, Ltd.