The use of hormonal contraception in women with headaches, especially migraine headaches, is an important topic. Approximately 43% of women in the United States report migraines.1 Roughly the same percentage of reproductive-aged women use hormonal contraception.2 Data suggest that all migraineurs have some increased risk of stroke. Therefore, can women with migraine headaches use combination hormonal contraception? And can women with severe headaches that are nonmigrainous use combination hormonal contraception? Let’s examine available data to help us answer these questions.
Risk factors for stroke
Migraine without aura is the most common subset, but migraine with aura is more problematic relative to the increased incidence of stroke.1
A migraine aura is visual 90% of the time.1 Symptoms can include flickering lights, spots, zigzag lines, a sense of pins and needles, or dysphasic speech. Aura precedes the headache and usually resolves within 1 hour after the aura begins.
In addition to migraine headaches, risk factors for stroke include increasing age, hypertension, the use of combination oral contraceptives (COCs), the contraceptive patch and ring, and smoking.1
Data indicate that the risk for ischemic stroke is increased in women with migraines even without the presence of other risk factors. In a meta-analysis of 14 observational studies, the risk of ischemic stroke among all migraineurs was about 2-fold (relative risk [RR], 2.2; 95% confidence interval [CI], 1.9–2.5) compared with the risk of ischemic stroke in women of the same age group who did not have migraine headaches. When there is migraine without aura, it was slightly less than 2-fold (RR, 1.8; 95% CI, 1.1–3.2). The risk of ischemic stroke among migraineurs with aura is increased more than 2 times compared with women without migraine (RR, 2.27; 95% CI, 1.61–3.19).3 However, the absolute risk of ischemic stroke among reproductive-aged women is 11 per 100,000 women years.4
Two observational studies show how additional risk factors increase that risk (TABLE).5,6 There are similar trends in terms of overall risk of stroke among women with all types of migraine. However, when you add smoking as an additional risk factor for women with migraine headaches, there is a substantial increase in the risk of stroke. When a woman who has migraines uses COCs, there is increased risk varying from 2-fold to almost 4-fold. When you combine migraine, smoking, and COCs, a very, very large risk factor (odds ratio [OR], 34.4; 95% CI, 3.27–3.61) was reported by Chang and colleagues.6
Although these risks are impressive, it is important to keep in mind that even with a 10-fold increase, we are only talking about 1 case per 1,000 migraineurs.4 Unfortunately, stroke often leads to major disability and even death, such that any reduction in risk is still important.