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Emergency Contraception

By Dawn Stacey M.Ed, LMHC, About.com

Updated: September 11, 2009

About.com Health's Disease and Condition content is reviewed by the Medical Review Board

Emergency Contraception

Photo © 2009 Dawn Stacey
What Emergency Contraception Is:
Emergency contraception (EC) is a birth control option that women can use to reduce the risk of pregnancy after unprotected sex or contraceptive failure. Emergency contraception has been available for more than 30 years and is a safe and effective method of birth control.

Also Known As:
  • EC
  • Plan B One-Step
  • Morning After Pill
  • Plan B
  • Postcoital Contraception

Available Forms of EC:
Emergency contraception is offered in three ways:

How Emergency Contraception Works:
Emergency contraception contains the same hormones that are found in birth control pills. The exact mechanism of action, though, is not clear. However, emergency contraception MAY help to reduce the risk of pregnancy by stopping ovulation, blocking fertilization, or by preventing the sperm from joining the egg. The mechanism likely depends on where in her menstrual cycle a women is.

Who Should Obtain EC:
Typically, women should obtain emergency contraception if there is a chance that pregnancy could occur due to contraception failing or unprotected sex.

Generally speaking, almost every female who needs emergency contraception can safely use it; this even applies to women who are not good candidates to use oral contraceptives as their main form of birth control. Emergency contraception can also be used safely by adolescents.

A woman may want to use emergency contraception if:
  • She miscalculated her “safe” days and had sex on a day that she may had been fertile

  • She did not use any birth control during sex

  • She forgot to take her normal birth control method (for examples, she missed a pill(s), did not insert her Nuvaring, or did not apply her birth control patch)

  • A condom broke or slipped off during sex

  • Her partner did not pull out in time

  • Her diaphragm, cervical cap, or shield moved out of place during sex or she forgot to add spermicide

  • She took the Today Sponge out too soon

  • She was forced into having unprotected sex

    When Emergency Contraception Should Be Started:
    In order to reduce the risk of pregnancy, emergency contraception should be started up to 5 days (120 hours) after unprotected sex. The sooner it is used, the better the chances of preventing pregnancy.

    With Plan B One-Step, you only need to swallow ONE pill. You should take the pill as soon as possible. The manufacturer suggests using Plan B One-Step within 72 hours of contraceptive failure or unprotected sex — but the sooner you take it, the more effective it'll be. However, the morning after pill may still be useful to take (hopefully to decrease your chances of pregnancy) for up to 5 days after unprotected sex.

    Misconceptions About Emergency Contraception:
    Emergency contraception is not the same thing as an abortion. Plan B One-Step is often confused with the abortion pill, RU486. These two medications serve two different purposes and work completely different from one another.

    Emergency Contraception cannot end a pregnancy or affect an existing pregnancy. Scientific and medical authorities are in agreement that emergency contraception reduces the risk of pregnancy and helps prevent the need for abortion.

    How to Obtain Emergency Contraception :
    Plan B One-Step is available at pharmacies without a prescription for men and women age 17 or older. Other forms of emergency contraception can be obtained by prescription, so these require a doctor's appointment.

    For those girls under 17, a prescription is also needed to purchase Plan B One-Step. As a precaution, those under the age of 17 can ask their doctors about getting a prescription for EC to have just in case an emergency occurs. This way, you will already have the prescription to fill immediately and will not need to wait to get a medical appointment.

    Effectiveness :
    In general, emergency contraception is meant to be a backup birth control method. It is not as effective as the correct and consistent use of other reversible prescription birth control methods. Additionally, emergency contraception does not continue to prevent pregnancy during the rest of the reproductive cycle, so other birth control methods must be used.

    Two main factors influence the effectiveness of emergency contraception:

    • The amount of time that has gone by since the incident of unprotected sex

    • The point in a woman's cycle when she had sex.
    Therefore, the sooner emergency contraception is used after unprotected sex, the more effective it is. Also, the effectiveness of emergency contraception decreases the closer a woman is to ovulation at the time of having unprotected sex.

    All methods of emergency contraception reduce the risk of pregnancy by 75-99% when they are initiated within 72 hours.

    Costs:

    The cost for emergency contraception varies widely and depends upon the method. Total fees can range from about $35-$45 (for Plan B One-Step) anywhere up to around $400 (to obtain ParaGard IUD).

    Side Effects:

    These, too, vary depending on the type of emergency contraception used. Women should discuss any major side effects with their doctor as well as if experiencing any signs of pregnancy after using emergency contraception. Some of the most common pregnancy signs include:
    • Missed menstrual period
    • Sore or enlarged breasts
    • Nausea
    • Frequent urination
    • Unexplained fatigue
    • Headaches

    STD Protection:

    No emergency contraception offer protection from STDs. Women who need emergency contraception may be at more risk for these infections. Women at the most risk are those who:
    • Have had unprotected sex with infected partners
    • Are victims of sexual assault
    • Who use IV drugs or have a partner who does
    Emergency contraception (in the form of hormonal pills) may be a safer choice for those women at increased risk for STDs instead of an IUD. This is because bacteria from a preexisting infection can be introduced into the uterus during IUD insertion. If this is left untreated, it can lead to pelvic inflammatory disease.

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