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Frequently Asked Questions on Emergency Contraception

What is Emergency Contraception (EC)?

Emergency contraception (EC), sometimes referred to as the "morning after pill", is a method of preventing an unintended pregnancy. It can be used up to 72 hours after unprotected sex or if there has been a contraceptive failure, such as a condom breaking, or missed birth control pills. In Canada, EC is sold under the name "Plan B". It is a hormonal method, similar to birth control pills, but taken in different doses.

How effective is EC?

When hormonal EC is taken within 72 hours (3 days) after unprotected sex, the risk of getting pregnant is reduced by approximately 75%. There has been some evidence that hormonal EC can be effective up to 5 days after intercourse. It is important to know that EC is more effective the sooner the drug is taken.

When would a woman need to use EC?

A woman might need to use emergency contraception after having sex when:

  • the condom broke
  • no birth control was used at all
  • two or more birth control pills were missed in a row or she was late for her depo-provera shot
  • the diaphragm slipped
  • she was forced to have sex

How do EC pills work?

It is not fully understood how EC pills work but it is believed that the hormones in the pills interfere with a woman's ovulation process to help prevent fertilization.

What if I think I might already be pregnant?

If EC is taken by a pregnant woman, the treatment will NOT work and it will not disrupt an established pregnancy. If you think you might be pregnant, see your family physician or health clinic.

Are there any side effects when taking EC?

The most common side effects experienced when taking EC are the following:

  • nausea and vomiting
  • irregular vaginal bleeding
  • fatigue
  • headache
  • dizziness
  • breast tenderness

Will EC prevent sexually transmitted infections (STI)?

EC does not protect against STI, including HIV transmission. Other measures should be taken for their prevention, such as using a condom when having sex, even if you are already using hormonal birth control. If you have had unprotected sex and are not sure of the health of your partner, you should visit your family physician or health clinic to discuss STI testing.

Where can I get EC?

As of April 2005, pharmacists across Canada have the authority to dispense EC without a written prescription from a physician.

Is EC the same thing as RU 486?

EC is NOT the same as the pill called RU 486. RU 486, also know as mifepristone or the "Abortion Pill", is used to initiate the termination of a pregnancy. EC does not interfere with an established pregnancy and does not harm a woman or her fetus if she takes EC while already pregnant.

What is an IUD?

An intrauterine device (IUD) can also be used as a method of emergency contraception when inserted by a physician up to 7 days after unprotected sex.

An IUD can prevent more than 99% of unintended pregnancies and also provides ongoing contraception when left inserted.

Side effects of an IUD can include pain or cramping, bleeding and an increased risk of acquiring pelvic inflammatory disease. If you choose to have an IUD inserted, your physician will discuss this with you.

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