Plan B helps prevent a pregnancy, not end one. Here's how it works.

·4 min read
Plan B is a commonly used emergency contraceptive, but how does it work? Experts explain how the
Plan B is a commonly used emergency contraceptive, but how does it work? Experts explain how the "morning-after pill" prevents pregnancy. (Photo: Getty Images)

Despite decades of evidence showing its safety and efficacy, Plan B remains the focus of much confusion. On top of myths about it impacting fertility, the emergency contraceptive is often mistaken for a form of abortion. Dr. Jessica Shepherd, a board-certified ob-gyn and chief officer of Very Well Health, says those statements are inaccurate. "Plan B is not an abortion pill and it will not be effective if you are already pregnant," Shepherd tells Yahoo Life. 

Dr. Mary Jane Minkin, clinical professor in the department of obstetrics, gynecology and reproductive sciences at the Yale University School of Medicine agrees. "Its mechanism of action is to prevent ovulation so that you won't release that egg if there is sperm hanging around."

Dr. Sherry Ross, women's health expert and author of She-ology, The Definitive Guide to Women's Intimate Health. Period, says the narrative needs to be changed. "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."

History of contraceptive pills

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 it impact one's ability to conceive later. 

Accessing emergency contraception

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 around Plan B. "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."

Shepherd agrees. "It is important for women to access this as there are instances of emergency contraception needs if your regular method of birth control failed or you had unprotected sex."

Overall, the experts urge anyone wanting to prevent a pregnancy to stick with facts. "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. 

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