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Answers to Frequently Asked Questions About…


Can emergency contraceptive pills cause birth defects?

No, emergency contraceptive pills ("morning after pills" or "day after pills") do not appear to cause any birth defects. Although no reliable studies have looked specifically at women who gave birth after using emergency contraception, strong reasons exist for concluding that emergency contraceptive pills will not harm a developing fetus.


In the case of progestin-only pills (like Plan B One-Step, Next Choice One Dose, or My Way), these pills contain the same hormones as many daily birth control pills, which a number of studies have found cause no increased risk of birth defects in children born to women who continued to take them because they didn’t realize they were pregnant. As a result, the United States Food and Drug Administration removed warnings about the possibility that oral contraceptives could harm a fetus several years ago. In addition, even if you don’t realize you are pregnant, you would take emergency contraceptive pills long before the organs would start to develop (a process called “organogenesis”), making it extremely unlikely that emergency contraception would lead to birth defects.


In the case of ulipristal acetate (ella), data are limited, but post-marketing surveillance after widespread use in Europe suggests that the drug would not harm an existing pregnancy.

A thorough and up-to-date academic review of the medical and social science literature on emergency contraception is available; click here for the PDF .


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