Health scare of the week: Birth control pills and glaucoma
A new study has found an association between the use of birth control pills and glaucoma.
Women who used birth control pills for three years or more had twice the risk of developing glaucoma, a leading cause of blindness. That’s the sobering conclusion of a new study analyzing data from 3,400 women ages 40 and older by the Centers for Disease Control and Prevention, which more than doubles previous estimates of such risk. Birth control pills lower women’s levels of the hormone estrogen, which is thought to have a protective effect on the eye, possibly making it more susceptible to glaucoma’s damage to the optic nerve. But researchers stress that the new data confirms only an association, not a direct cause, and even at the higher risk estimate, the chance of women getting glaucoma after 40 remains a little under 4 percent. Still, “if you’ve been using oral contraceptives for a long time, that may be enough indication for you to get screened for glaucoma,” University of California, San Francisco, ophthalmologist Shan Lin tells NPR.org. Glaucoma affects 60 million people worldwide, and while there are treatments to slow its progression, there is no cure.