We have reviewed the reports of 129 young women complaining of migraine and 100 with neurologic and ophthalmic diseases which developed while they were using oral contraceptives. Four of the cases reviewed are given here as case reports. In roughly 26% of the stroke patients the area affected was supplied by the vertebro-basilar-posterior-cerebral artery distribution. In more than one half of the patients with serious sequelae a significant history preceeded serious illness. Analysis of history of users of oral contraceptives in whom serious neurologic disease developed while taking the medication indicates that patients with hypertension, vascular disease, migraine, facial paralysis, endometriosis, and neurologic disease may be particularly prone to difficulties while taking the contraceptive pill. Transient ischemic attacks while taking the pill invariably resulted in strokes.