Many women ask themselves and their doctors which forms of contraception are most effective. The answer might not be what you think. 

Taraneh Shirazian, MD, an assistant professor in NYU Langone’s Department of Obstetrics and Gynecology, and a gynecologist at the Joan H. Tisch Center for Women’s Health, spoke with Business Insider to lay the question to rest. “The most effective method of contraception is the one that doesn’t rely on you,” Dr. Shirazian says. 

She explains the difference between two forms of contraception: the birth control pill and the intrauterine device (IUD). The pill, says Dr. Shirazian, is only as effective as its user remembering to take it daily. By contrast, “you don’t have to remember to take [the IUD]…it’s the most effective.”  

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