Healthy women who take the newer, lower-dose birth control pills are not increasing their risk of stroke, finds a new study.
Ever since birth control pills debuted in the 1960s, doctors have worried the pills could increase a woman's risk of stroke. Most studies looking at the link, however, have looked at women who took early forms of the pill, which contained higher levels of estrogen compared to those in use today. Whether lower dose pills confer the same risk has been unclear, but most doctors have continued to recommend the pill only for healthy, younger women just to be safe.
In this study, researchers from Australia conducted detailed interviews with 234 women ages 15 to 55 who had experienced a stroke and 234 others who had not experienced a stroke. All were asked to provide a history of birth control pill use, along with information on other health conditions and health-related lifestyle factors.
Results showed no statistically significant stroke risk related to the use of lower-dose birth control pills nor was there a link seen between years of pill use and the risk of stroke. Women who smoked, however, had about four-times greater risk of stroke as nonsmokers, although the risk dropped considerably among former smokers. Women with known stroke risk factors, such as high blood pressure, had about twice the risk.
The researchers conclude otherwise healthy women who do not smoke run few stroke risks from taking oral contraceptives. However, women with conditions known to increase stroke risk, such as high blood pressure, a family history of stroke, and diabetes, should be prescribed the pill with caution.