Commonly referred to as “the morning after pill” (a somewhat misleading expression because it can be effective for up to 72 hours), this contraception method consists of several tablets that work by giving the body a strong, short burst of synthetic hormones that disrupt the hormone patterns needed for pregnancy.
Following use of this medication, the next menstrual period may come on time, or be a little early or a little late. 95% of women using this medication will have their next periods within 7 days of the expected time. The next period may be of average heaviness and duration, or it may be heavier or lighter. If the next period is more than 7 days late, a pregnancy test should be performed.
When a woman is concerned about contraceptive failure, or has unprotected sexual intercourse, there are a few basic steps necessary before emergency contraception is taken. Patients who are already established with a physician or other health care provider should simply phone the office that day (or the next morning) and request emergency contraception. Most doctors will require a pregnancy test to insure you are not already pregnant from intercourse that occurred over the past few months. Some will require a physical exam, but this is not universal.
The most common method of emergency contraception is the “Yuzpe” method, named after a Canadian gynecologist. This method involves taking a specific number of birth control pills 12 hours apart. It is thought to work in two ways. The first is to render the inside lining of the uterus inhospitable to the egg. The microscopic egg passes out of the body unnoticed. This method also may block ovulation so that the ovary does not release an egg at all. As this method is quite safe, any woman who is not already pregnant can use this method within 72 hours of unprotected intercourse. Women taking other medications or being treated for medical problems should always discuss new medications with their doctor.