What is emergency contraception?

Emergency contraception (EC)--also called the "morning after pill"--is a form of birth control that may be used by women within 120 hours of having unprotected sex. There are two types of EC pills available in the United States: progestin-only (such as Plan B One-Step® or Next Choice®) and ulipristal acetate (ella®).

If dedicated EC pills are unavailable, women can—under a doctor’s care--use higher doses of certain regular oral contraceptives. This course of treatment is also called the Yuzpe regimen. However, ulipristal and progestin-only methods are preferred over the Yuzpe regimen. Not only are they more effective, but they also cause minimal side effects such as nausea and vomiting (which are common with high dose combined birth control pill regimens).

Another option for emergency contraception is insertion of a copper IUD into the uterus within five days of unprotected sex. The copper IUD is 99.9% effective at preventing pregnancy when inserted after sex. It provides at least 10 years of excellent ongoing contraception.

How does emergency contraception work?

EC pills work mainly by disrupting or preventing ovulation.

How is emergency contraception available?

Progestin-only EC pills are available over-the-counter without age restrictions to women and men. Look for the brand names Plan B One-Step, Take Action®, Next Choice One-Dose, My Way® or other generics in the aisles near the pregnancy tests and ovulation kits. Sometimes EC pills may be locked up behind the pharmacy counter.

Ulipristal acetate is available by prescription only for patients of all ages.

How effective is emergency contraception?

EC pills are about 89 percent effective when taken within 72 hours of unprotected intercourse. The prescription brand ella® is more effective than the over-the-counter methods such as Plan B One-Step or Next Choice because it works closer to the time of ovulation. However, any EC pills should be taken as soon as possible after unprotected sex to be the most effective. All EC pills can be taken within five days of intercourse.

Over-the-counter EC pills might be less effective in women who are overweight or obese. If you are overweight, consider contacting your doctor about prescription ella® or a copper IUD. If you don’t think you can get one of these more effective products within five days from your doctor, go ahead and take the over-the-counter product anyway.

Currently, in the United States, there are no EC methods that are 100 percent effective. Therefore, if you think you might be pregnant, you should take a pregnancy test even if you have taken an emergency contraceptive method.

Is emergency contraception the same thing as abortion?

No. Emergency contraception is not abortion. Emergency contraceptive pills work by trying to prevent the egg and sperm from meeting, delaying ovulation. If emergency contraception were similar to abortion, it would be 100 percent effective at preventing pregnancy.

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