Background: Migraine is common among women of reproductive age and is associated with an increased risk of ischemic stroke. Combined oral contraceptives (COCs) are also associated with an increased risk of ischemic stroke. Use of hormonal contraception among women with migraine might further elevate the risk of stroke among women of reproductive age.
Objective: To identify evidence regarding the risk of arterial thromboembolism (stroke or myocardial infarction) among women with migraine who use hormonal contraceptives.
Methods: We searched the PubMed database for all articles published from database inception through January 2016. We included studies that examined women with migraine overall or separated by subtype (with or without aura). Hormonal contraceptives of interest included combined hormonal methods (COCs, patch and ring) and progestin-only methods (progestin-only pills, injectables, implants and progestin intrauterine devices).
Results: Seven articles met inclusion criteria. All were case-control studies of fair to poor quality reporting on use of COCs or oral contraceptives (OCs) not further described and all reported stroke outcomes. Four studies demonstrated that, among women with migraine (not separated by subtype), COC use was associated with approximately two to four times the risk of stroke compared with nonuse. The only study to examine specific migraine subtypes found an elevated risk of stroke among women with migraine with aura, and this risk was similar regardless of OC use, although these odds ratios were not reported. Two studies did not report risks among women with migraine and COC use combined, but both found increased risks of stroke with migraine and COC use independently. No evidence was found on other hormonal contraceptives or on risk of myocardial infarction.
Conclusion: Limited evidence suggests a two- to fourfold increased risk of stroke among women with migraine who use COCs compared with nonuse. Additional study is needed on the risks of hormonal contraceptives, including combined and progestin-only methods, among women with different migraine subtypes.
Keywords: Combined oral contraceptives; Migraine; Stroke; Systematic review.
Published by Elsevier Inc.