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Birth Control Overview (cont.)

What emergency contraception is available to prevent pregnancy?

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 there is a condom failure, following a sexual assault, or on any occasion following unprotected sexual intercourse. 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. 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 have had unprotected sexual intercourse may elect to use emergency contraception 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 employed. A woman will never know whether the pill prevented an unwanted pregnancy.

Emergency contraception should not be used as an ongoing birth control 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 found in standard birth control pills. There are few known risks in emergency hormone pill regimens, because the high-dose of hormones is short lived. Several cases of deep vein thrombosis (blood clotting) have been reported in women using this emergency method. These pills will not work to 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 following unprotected intercourse. The mode of action of this pill regimen has not been clearly established. A menstrual period and fertility return with the next cycle.

  • Effectiveness: Some studies show that they are effective if taken after that period of time, but such off-label use should not be encouraged.
  • Cons: The Plan B method is 1 dose of levonorgestrel taken as soon as possible, but no later than 48 hours after unprotected sex, with a second dose taken 12 hours later.

Copper T380 intrauterine device: The Copper T380 IUD can be inserted as many as 7 days after unprotected sexual intercourse to prevent an unwanted pregnancy.

  • Effectiveness: 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 pregnancy rate, 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 ongoing birth control.
  • Pros: 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%.
  • Cons: Some women may feel nausea and experience vomiting. There may be minor changes in your menstrual period, some breast tenderness, fatigue, headache, abdominal pain, and dizziness. Ectopic pregnancy is possible if a treatment failure occurs. This is a life-threatening condition. Emergency contraception does not protect against STDs.
Medically Reviewed by a Doctor on 8/26/2016
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