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revised Friday October 12 2007

Plan B - Emergency Contraceptive Pill

What is Plan B?

Plan B is an emergency method of contraception which contains a hormone called progestin. Generally, women who can safely take the birth control pill may use Plan B. Plan B must be prescribed by a health professional.

To prevent pregnancy, Plan B must be started within 72 hours after unprotected intercourse has occurred. Plan B can be used if:

  • a condom broke or slipped
  • you used withdrawal or no contraception at all
  • you missed some birth control pills and didn't use a condom
  • you were late getting your Depo injection
  • your diaphragm slipped
  • you were sexually assaulted

Plan B works by preventing the release of an egg from the ovary, by preventing sperm and egg from meeting or by preventing a fertilized egg from attaching to the wall of the uterus. Plan B is 95% effective if taken properly within 24 hours of unprotected sexual intercourse, 85% if taken within 25-48 hours and 58% if taken with 49-72 hours. Plan B does not protect against sexually transmitted infections and HIV.

If you are already pregnant Plan B will not cause an abortion and is not known to harm the fetus.

How to use Plan B

You will receive 2 pills in a package. Read the enclosed information carefully.

  • Eat something and take the first pill as soon as possible.
  • 12 hours later, eat again and take the second pill. (Time it so you don't have to wake up in the middle of the night!) If you felt sick with the first pill, you may want to take an anti-nausea pill such as dimenhydrinate (or Gravol) before you take the second pill.
  • The most common side effect is nausea. Very few women (6%) who take Plan B will vomit. Taking Plan B with food will help with the nausea. If you vomit within one hour of taking either the first or second pill, call the clinic/walk-in/doctor to see if you need another dose. If you vomited due to an upset stomach and you can see the pill in the vomit, a replacement dose is necessary. If you can't see the pill or if it is more than one hour, a replacement dose is not needed.
  • Other possible side effects are mild abdominal pain, fatigue, headache and spotting or bleeding from the vagina. These symptoms are temporary, usually lasting only a few days.
  • See a doctor immediately if you have itching all over your body or cramping/severe abdominal (stomach) pain before your next period.
  • Your next menstrual period should begin at its expected time. If it is more than 1 week late, or if it is very different from normal, call the clinic for an appointment and pregnancy test.

Can I have Plan B to Use in the Future?

In certain situations you may be offered Plan B to use at a later date. Remember to:

  • store Plan B in a safe place, away from children.
  • make sure of the reasons why you need to use it.
  • check the expiry date before using it.
  • follow the instructions carefully for taking it.

If you have any questions when you are taking it, call a health professional.

What about Ongoing Birth Control?

Plan B will not protect you from pregnancy during the rest of this menstrual cycle. Another method of birth control, such as condoms, MUST be used until your next period. Plan B is not recommended as a regular method of birth control. Speak to a health professional about an ongoing method. Plan B will not affect your ability to get pregnant in the future.

If you are taking Plan B because you missed some birth control pills, and you missed:

  • 1, 2 or 3 pills: Do not take any of the missed pills. Take the Plan B and then continue on your pack on the day after you take the second Plan B. Use condoms for at least the next 7 days.
  • 4 or more birth control pills: Speak with a health professional for advice on restarting the birth control pills.

Remember: Since you have had unprotected sex, you should consider being tested for sexually transmitted infections (STIs).

For more information, call 905-799-7700 and ask for Sexual Health Information.

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Revised: Friday October 12 2007

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