Plan B is an emergency contraceptive not an abortion pill. Experts explain the difference.

A Plan B One-Step emergency contraceptive box is seen in New York, April 5, 2013. A federal judge on Friday ordered the U.S. Food and Drug Administration to make
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If you've been told that Plan B is a contraceptive — a drug that prevents pregnancy — you may have been confused by the video Rep. Marjorie Taylor Greene shared on her Twitter Thursday. "The Plan B pill kills a baby in the womb, once a woman is already pregnant," Greene says in the video. Her words were delivered as part of a speech the polarizing lawmaker gave in opposition to a bill that would give veterans free access to contraceptive care. But her thoughts on Plan B, experts tell Yahoo Life, are dangerously misinformed.

"Plan B certainly does not kill babies," says Dr. Mary Jane Minkin, clinical professor in the department of obstetrics, gynecology and reproductive sciences at the Yale University School of Medicine. "Its mechanism of action is to prevent ovulation so that you won't release that egg if there is sperm hanging around," she adds.

Dr. Sherry Ross, women's health expert and author of She-ology, The Definitive Guide to Women's Intimate Health. Period, agrees. "It’s completely medically inaccurate to call Plan B an abortion pill nor does it kill a baby in the womb," says Ross. "Plan B works by preventing a woman from ovulating so there is no egg released. If there is no egg released, you cannot get pregnant by the sperm."

Emergency contraceptive pills have been around for decades and were first approved by the Food & Drug Administration in 1998. Plan B has been available over the counter (meaning without a prescription) in the U.S., except for young women under 17, since 2013. That same year, the National Center for Health Statistics estimated that 11 percent of women age 18-44 who were sexually active had used a morning-after pill, or a total of 5.8 million women.

Minkin says it remains widely accepted. "It is quite a safe medication — it is just a synthetic form of progesterone, which is what our bodies make when we ovulate." The synthetic hormone she's referring to is what's known as levonorgestrel, an active ingredient in birth control pills for over 30 years, the FDA notes. If taken within 72 hours of unprotected sex, levonorgestrel can inhibit ovulation, thereby preventing pregnancy.

Planned Parenthood elaborates on the medicine's use on its website, noting, "If you use emergency contraception correctly after you have unprotected sex, it makes it much less likely that you’ll get pregnant." Studies have shown that the drug is safe and does not cause any longterm side effects, nor will impact one's ability to conceive later on (a common myth that circulates about the drug).

Minkin says those who wish to avoid pregnancy should have access to it, but also stresses that it should not be considered the main form of birth control. "I think it's great for women to have access to it — if they've had an 'oops' moment and had unprotected intercourse," says Minkin. "However, I would strongly encourage all women to have a good contraceptive measure that they use all the time so they don't have to worry about thinking about it on a regular basis. We have lots of really great methods of long-acting reversible contraception that act on a long-term basis and you don't have to worry about day-to-day."

A spokesperson from the American College of Obstetricians and Gynecologists shared a practice bulletin with Yahoo Life specifically addressing confusion like Greene's. "Emergency contraception sometimes is confused with medical abortion," the document reads. "Medical abortion is used to terminate an existing pregnancy, whereas emergency contraception is effective only before a pregnancy is established. Emergency contraception can prevent pregnancy after sexual intercourse and is ineffective after implantation. Studies of high-dose oral contraceptives indicate that hormonal emergency contraception confers no risk to an established pregnancy or harm to a developing embryo."

Overall, the experts say that it's important the statements like Greene's are corrected. "We don't want things misrepresented to scare women from using effective forms of contraception," says Minkin.

"Plan B is safe and — when taken correctly — can prevent an unplanned pregnancy safely," adds Ross. "Politicians should never have an authoritative voice in making medical comments or recommendations for women, especially when they haven’t done their homework."

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