Before you take emergency contraceptive pills (ECPs), be sure you understand both the benefits and the possible problems of using ECPs. This fact sheet also lists the danger signs you should watch for. If you have any questions as you read, we will be happy to talk about them with you.

Emergency contraceptive pills (ECPs) are hormonal pills (similar to birth control pills) that you take to try to prevent pregnancy after you have unprotected vaginal intercourse (birth control method fails, no birth control method used).

The pills either keep the ovary from releasing an egg, thicken cervical mucus or change the lining of the uterus in such a way that a fertilized egg may not attach and develop into a pregnancy.

The pills should be started preferably within 72 hours (3 days) or up to 120 hours (5 days) of unprotected vaginal intercourse. The sooner they are taken, the more effective in preventing pregnancy they will be.

You will get the FDA approved information provided by the pill manufacturer if you get these pills at Planned Parenthood. If you get your pills elsewhere, you should also get a copy of the FDA information. You should read the information and ask questions about anything you do not understand.

These emergency pills prevent pregnancy about 76-99% of the time, depending on when, in the cycle, unprotected intercourse takes place. However, this method fails to prevent pregnancy in some cases, because:

A sensitive urine pregnancy test should be done before taking ECPs if you think there is any chance that you could already be pregnant (last period was late, light, or short, or if you feel pregnant).

You should not use these Pills if you are (or think you are) already pregnant. However, if you are pregnant, or if the pills fail and pregnancy occurs, there have not been any reports of serious side effects to the woman or to the fetus from taking the pills.

Rare but serious problems or complications, particularly with blood clots, can occur with the regular use of birth control pills, as stated in the FDA information. It is not known whether blood clotting problems (or other complications) can also occur when birth control pills are used for emergency contraception, but medical experts do not think so because the exposure to the pills is so short.

Some reactions to these pills (for about 24 hours) may include:

Your next period could be early or late, or could be lighter or heavier. If you use ECPs more than once in a monthly cycle, the chance of having problems with your next period will be even greater.

If you see a clinician for any reason before you get your next period, you should tell him/her that you have taken ECPs.

It is important to think of a more reliable form of ongoing birth control if you are at risk of unintended pregnancy. After using ECPs, some women continue on birth control pills or use an IUD. Ask about the options at your Planned Parenthood clinic.

Having unprotected sex may have put you at risk for sexually transmitted infections (STIs) and a serious infection could cause sterility. If you think you could be at risk for STIs, you should talk to your clinician about getting tested.

You should come back to the clinic four weeks after taking these pills for a checkup if you have not had a normal period, or if you feel like you could be pregnant, or if you have any early signs of pregnancy (such as feeling sick to your stomach, feeling very tired, breast swelling or tenderness).

  Emergency Contraception