Emergency Contraceptive Pills (ECPs)

Birth Control "The Morning After"

What are Emergency Contraceptive Pills?

Emergency Contraceptive Pills (ECP), or The Morning-After "Pill," are actually a large dose of ordinary oral contraceptives taken after intercourse has occurred. ECPs were first used in the 1960's for rape victims, but the FDA now recommends oral contraceptives for emergency use when a woman has had unprotected intercourse within the previous 72 hours. ECPs are thought to be effective for up to 120 hours (5 days) after unprotected sex. Unprotected sex means that contraception was used incorrectly or not at all, or that the contraceptive method failed (i.e. the condom broke or a female barrier device slipped out of place).

Reasons Women Request Emergency Contraception

  • No Birth Control Used: 55%
  • Barrier Method Failed: 35%
  • Other: 10%

In the United States, ECPs are marketed under the name Plan B. The oral contraceptive Preven had once been FDA approved for this use, but it was withdrawn from the market in 2004. In addition to Plan B, over twenty brands of OCs can be used for emergency contraception if taken in higher doses.

How do Emergency Contraceptive Pills work?

It takes only a few minutes for sperm to enter the uterus, and if a woman has ovulated, fertilization may occur in just a few hours. ECPs work in the same way as other hormonal methods, by suppressing ovulation (if it has not yet occurred), interfering with the movement of the ovum, and making it difficult for the embryo to implant in the uterus (if fertilization has occurred) [more about this]. For women who have had unprotected intercourse and do not wish to use ECPs, it is suggested that immediately following unprotected intercourse a spermicidal agent be applied to reduce the probability of conception. However, this will not prevent pregnancy if fertilization has occurred.

How to Obtain Emergency Contraceptive Pills

Emergency Contraceptive Pills were available only by prescription until 2006, when the FDA approved the sale of ECPs over-the-counter from a pharmacist. ECPs can be purchased at any drug store that has a pharmacist on duty. Women under the age of 18 must still obtain a prescription before purchasing ECPs.

Safety & Effectiveness of Emergency Contraceptive Pills

Emergency Contraceptive Pills are thought to be 74% effective when taken within 72 hours, and somewhat less effective when taken between 72-120 hours after sexual contact. The more time that has passed since unprotected sex, the less effective the ECPs. Women who test positive for pregnancy despite the use of ECPs may be concerned about the effect of the pills on the pregnancy, and therefore consider abortion. Fortunately, there is no evidence that ECPs will harm a developing baby once implantation has occurred. Common side effects are nausea and vomiting and menstrual cycle disturbances. Health risks may include an increased risk of ectopic (tubal) pregnancy.

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