Oral contraceptives and stroke in young women. Associated risk factors.

Oral contraceptive use alone, in the absence of smoking, hypertension, or migraine, significantly increases the risk of stroke. Regardless of use or nonuse of these agents, hypertension is a risk factor for development of either thrombotic or hemorrhagic stroke. Regular cigarette smoking and a history of symptoms indicative of migraine also increase the likelihood of one or the other type of stroke, but more information is needed before a definite relationship can be established between these clinical factors and cerebrovascular disease.