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Emergency Contraception is now available over-the-counter!


I just heard that "The Morning After Pill" can now be bought at a drugstore without a prescription! You don't even have to talk with a pharmacist any more. I think that's great. I've had a major hassle in the past when I tried to get it-somehow I felt like I was being a kind of bad girl.

Even though I've used it once, I still have a few questions: How does this Morning After Pill actually work? Will it cause my periods to change? What side effects could I experience if I needed to use it again? And, should I have some on hand, just in case?


Thanks for your good questions about Emergency Contraception. We at CeMCOR are rejoicing that it is now available without any barriers. I'm sorry that you previously found it difficult to get Emergency Contraception. In both the USA and Canada, its availability has been limited by certain points of view about women and reproduction -I'll describe these below. Before I can answer your questions, however, I need to explain what Emergency Contraception is and little of the history that led to our now having it freely available.

What is Emergency Contraception?

The over-the-counter form we have in Canada is called "Plan B." It contains a high dose progestin (a synthetic form of progesterone). Plan B is levonorgestrel in two pills taken 12 hours apart, each containing 0.75 mg. To be most effective, we must start Plan B as soon as possible after unprotected intercourse (within 24 hours it is 95% effective). It is really only effective if it is taken within 3 days (72 hours) during which time it has an average 83% effectiveness at preventing pregnancy (1).

Earlier kinds of emergency contraception contained high doses of estrogen as well as progestin and caused significant nausea and vomiting (1). Plan B is much safer and easier to take, which led to its being made available without a prescription, but with pharmacist counseling, in Canada in 2000.

Because some pharmacists wrongly believed that Plan B caused abortion, or because pharmacists with counseling training were commonly unavailable, other women, like yourself, have reported difficulty obtaining it (2). The controversy over a news/feature article describing this "hassle" in the Canadian Medical Association Journal led eventually to the firing of the Editor and Associate Editor and eventually to the total restructuring of our major Canadian general medical journal. It also raised real concerns about undue influence of the Canadian Medical Association and the Canadian Pharmaceutical Association on freedom of scientific publication. Interestingly, a parallel issue occurred in the U.S.A. where two different scientific panels independently approved Plan B for over-the-counter use, but the Food and Drug Administration (FDA) stalled for years in approving it. Eventually a vocal woman FDA scientist resigned in protest and began speaking about the (apparent) White House interference with scientific decisions related to women's contraception. It is now approved as over-the-counter in the USA but only for women ages 18 and older. Apparently availability differs by State.

How does Emergency Contraception work?

Emergency Contraception works to prevent pregnancy in two main ways: to prevent the release of an egg through either suppressing the hormonal events that are necessary before ovulation, or by preventing the sperm meeting up with the egg. High levels of progestin in Plan B, through feedback to the brain, either prevent the midcycle estrogen peak or stop the LH peak from occurring (depending when in the menstrual cycle Plan B is taken). Both of these hormonal peaks are necessary to trigger ovulation. Plan B also works to prevent sperm swimming up into a Fallopian Tube to meet the egg. It does this by putting a roadblock at the opening of the uterus! Like natural progesterone, Plan B makes the mucus from the cervix (mouth of the uterus) thick or sticky. Sperm can't swim through this, get into the uterus, and from there up into the tube where fertilization usually takes place. Although progestins do thin the uterine lining, they require high levels for many days to do this. Therefore, Plan B doesn't cause failure of implantation of a fertilized egg-in other words, it doesn't cause an abortion.

Will Plan B cause my periods to change?

The short answer is, "maybe a little." It might cause some spotting in the period in which you take it. It can cause your new flow to start a few days early or a few days late. Usually after that the timing and the amount of flow will return to your own normal.

Will Plan B cause either temporary or permanent side effects?

Many young women report feeling bad about needing to use Plan B or are very concerned that they might have health risks from it (3). Some tend to confuse Emergency Contraception with the Pill. However, Plan B is quite different because it is only progestin, and it is only taken over 12 hours. The most commonly reported side effect is generally mild with about a quarter or a third of women having some nausea or intestinal discomfort.

In summary, over-the-counter availability of Emergency Contraception is a major advance for women in Canada. By definition, "emergency" is something that you don't expect to happen. Otherwise, use of an androgenic (male-hormone-like) progestin might be something you would avoid. Because no contraceptive method is perfect, having Plan B easily available without a prescription, or better yet, on hand, is a very good idea. If the condom breaks, the diaphragm slips, you forget to take a pill of your low dose oral contraceptive, or you have unprotected sex for any reason, you can breathe a sigh of relief knowing that you have a back-up plan to safely and effectively prevent unwanted pregnancy.

Hope this is helpful for you.

All the best,

Jerilynn C. Prior, MD, FRCPC


Additional resources


  1. Ho PC, Kwan MS. A prospective randomized comparison of levonorgestrel with the Yuzpe regimen in post-coital contraception. Hum Reprod 1993; 8(3):389-392.
  2. Counter attack. CMAJ 2006; 174(2):211-212.
  3. Shoveller J, Chabot C, Soon JA, Levine M. Identifying barriers to emergency contraception use among young women from various sociocultural groups in British Columbia, Canada. Perspect Sex Reprod Health 2007; 39(1):13-20.
Updated Date: 
Tuesday, November 19, 2013 - 13:30

Estrogen’s Storm Season: Stories of Perimenopause

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