Emergency Contraception

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What Is It?

Emergency contraception is a way to prevent pregnancy after unprotected sex. Often called the morning-after pill, emergency contraception pills (ECPs) are hormone pills that women can take after having sex. There are different types of ECPs. One type, levonorgestrel (brand names: Plan B and Next Choice), has been on the market for a while. It works best up to 72 hours after having unprotected sex, but will reduce the risk of pregnancy if taken within 120 hrs (5 days) after unprotected sex.

The other type, ulipristal acetate (brand name: ella), can be taken up to 5 days after unprotected intercourse.

Levonorgestrel ECPs are often available without a prescription to those 17 years and older. Prescriptions are required for those 16 and under, as well as for ulipristal. Recently, the FDA approved Plan B One Step to be sold over-the-counter without a prescription or age requirement.

The intrauterine device (IUD) can sometimes be used as a form of emergency contraception. This is rarely prescribed for teens, though.

How Does It Work?

Levonorgestrel progesterone-like hormone that is given in a high enough dose to prevent pregnancy. The number of pills taken depends on the type of pill being used. This type of ECP is most effective when it is taken as soon as possible after intercourse, although it can still reduce the risk of pregnancy when taken up to 120 hours after intercourse.

ECPs work by delaying ovulation (the release of an egg during a girl's monthly cycle). If fertilization and implantation have already happened, levonorgestrel won't interrupt the pregnancy.

The newer type of ECP, ulipristal acetate, is a different type of medication. It delays ovulation and may help prevent implantation. This type stays effective up to 5 days after unprotected intercourse.

Emergency contraception will not prevent pregnancy if a girl has unprotected sex after taking the ECPs.

How Well Does It Work?

About 1 or 2 in every 100 women who use ECPs will become pregnant despite taking ECPs within the recommended amount of time. The effectiveness of emergency contraception methods is calculated differently from the effectiveness of other contraceptives because of how they are used. Emergency contraception is the only type of contraception method that is used after unprotected sex.

Because emergency contraception does not prevent all pregnancies, a woman should see her doctor if she doesn't get her next expected period after taking it.

Protection Against STDs

Emergency contraception does not protect against sexually transmitted diseases (STDs). Couples having sex must always use condoms to protect against STDs even when using another method of birth control. If a condom breaks (or a couple has unprotected sex), it's a good idea to get tested for STDs.

Abstinence (not having sex) is the only method that always prevents pregnancy and STDs. If a girl has been forced to have unwanted sex, she should see a doctor right away to be tested for STDs. That's because it's important to treat some STDs immediately before they develop into bigger problems.

Possible Side Effects

Many girls who take emergency contraception pills experience side effects such as nausea, vomiting, breast tenderness, abdominal pain, headache, dizziness, and fatigue. Such side effects are usually minor, and most improve within 1 to 2 days. A girl's menstrual period may be temporarily irregular after taking ECPs.

Who Uses It?

Emergency contraception is not recommended as a regular birth control method. Instead, it is used for emergencies only. If a couple is having sex and the condom breaks or slips off, if a diaphragm or cervical cap slips out of place, or if a girl forgot to take her birth control pills for 2 days in a row, a girl may want to consider using emergency contraception. It is also available to teens who are forced to have unprotected sex.

Emergency contraception is not recommended for girls who know they are pregnant.

How Do You Get It?

Emergency contraceptive pills are currently available at drug stores or family planning clinics for anyone 17 or older without a prescription. Younger teens can only get ECPs with a doctor’s prescription. Recently, the FDA approved Plan B One Step to be sold over-the-counter without a prescription or age requirement. Ulipristal still requires a prescription for all ages.

How Much Does It Cost?

Depending on the types of pills, the emergency contraception pill costs between $10 and $80. Many health insurance plans cover the cost of emergency contraception and family planning clinics (such as Planned Parenthood) may charge much less.

Reviewed by: Mary L. Gavin, MD
Date reviewed: July 2013




Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
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