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Birth Control Overview (cont.)

Emergency Contraception

Emergency contraception (birth control after sexual intercourse) is defined as the use of a drug or device to prevent pregnancy after unprotected sexual intercourse. Emergency contraception can be used when a condom breaks, after a sexual assault, or any time unprotected sexual intercourse occurs. An example is the “morning after pill.”

 Unwanted pregnancy is common. Worldwide, about 50 million pregnancies are ended each year. In the United States each year, the widespread use of emergency contraception may have prevented over 1 million abortions and 2 million unwanted pregnancies that end in childbirth. Emergency contraceptives available in the United States include the emergency contraceptive pills and the Copper T380 IUD. A number of brands of "morning after" contraceptives are available without a prescription. Women who may become pregnant and who have had unprotected sexual intercourse may elect to take emergency contraceptive measures within the following 72 hours (3 days). There are no specific signs and symptoms of pregnancy during the first 2-3 days, when the morning-after pill needs to be used. A woman will never know whether the pill prevented pregnancy.

 However, emergency contraceptives should not be used as a contraceptive method if you are sexually active or planning to be because they are not as effective as any ongoing contraceptive method. The “morning after pills” contain high doses of the same hormones in birth control pills. There are no known risks because the high-dose of hormones is short lived. There are cases of deep vein thrombosis (blood clotting) in women using the emergency method. Neither of these pills will terminate an existing pregnancy.

Emergency contraceptive pills and the mini-pill emergency contraception method

The emergency contraception pills (Preven) use 2 birth control pills, each containing ethinyl estradiol and norgestrel, taken 12 hours apart for a total of 4 pills. The first dose should be taken within the first 72 hours after unprotected intercourse. Some studies show they are effective if taken after that period of time, but use should not be encouraged. The Plan B method is 1 dose of levonorgestrel taken as soon as possible and no later than 48 hours after unprotected sex and a second dose taken 12 hours later. It’s not clear how these pills work. If taken before ovulation, both methods may stop the egg from developing. If taken after ovulation, the emergency methods may stop a fertilized egg from implanting. A menstrual period and fertility return with the next cycle. Copper T380 intrauterine device: The Copper T380 IUD can be inserted as many as 7 days after unprotected sexual intercourse to prevent pregnancy. Insertion of the IUD is significantly more effective than the emergency contraception pills, reducing the risk of pregnancy following unprotected sex by more than 99%.

  • How effective: Emergency contraceptive pills are effective 55-94% of the time but most likely about 75% of the time. The effective rate of 75% does not mean a 25% failure rate. Instead, when considering 100 women who have had unprotected sexual intercourse during the middle 2 weeks of their cycle, about 8 will become pregnant. Of those 8 who have used emergency contraception, 2 will then become pregnant. Despite this significant reduction in the rate of pregnancy, women must understand that this method of contraception should be used only in emergencies and that they should be encouraged to use other more consistent forms of birth control.
  • Disadvantages: Some women may feel nausea and vomit. There may be minor changes in your menstrual period, some breast tenderness, fatigue, headache, abdominal pain, and dizziness. Ectopic pregnancy is possible if treatment fails. This is a life-threatening condition. You need emergency medical care. Emergency contraceptives do not protect against STDs.

See Emergency Contraception for more information.

Medically Reviewed by a Doctor on 6/24/2016
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