6th March 2013 | by MFC Team
Emergency contraception can be used to prevent pregnancy
There are a number of effective methods of birth control that can be used to prevent a pregnancy before having intercourse (e.g., birth control pill, condoms, diaphragm, etc.). However, in cases of unplanned or nonconsensual sex, or when birth control may have failed (e.g. broken condom), emergency contraception (EC) options exist for preventing pregnancy. Although there are several different types of EC, they primarily fall into two categories – the intrauterine device (IUD) and oral pills (e.g., levonorgestral, ulipristal acetate, combined oral contraceptive pills, and less commonly, mifepristone). Although it is currently unknown precisely how EC options work to prevent pregnancy, most are believed to work by preventing or delaying ovulation. Oral EC medication may also alter a woman’s hormone levels, while an IUD alters the environment in the uterus and endometrium, inhibiting fertilization.
The IUD is a copper T-shaped device that is inserted into a woman’s uterus, through her cervix. It is currently the most effective EC method, and can be effectively used up to five days after unprotected sex. In one study, only 10 out of 7034 female patients using the IUD for EC purposes became pregnant (failure rate of 0.14%). The IUD can also be used for up to 12 years as a method of planned birth control. A medical professional is required to insert the device into a woman’s uterus. Common side effects reported by women using the IUD include pain when having the IUD inserted and heavier periods.
Levonorgestral (LNG) – otherwise known by its brand-name “Plan B” or “the morning after pill” – is a progestin-only pill that is believed to work by delaying ovulation. It is the most common EC pill. It is also the only EC pill that is widely available over the counter, in pharmacies in Canada, Europe, and some US States. In some locations, LNG and other oral ECs may require a doctor’s prescription. Since its effectiveness decreases over time, it is best to take LNG as soon as possible. In one study, the effectiveness rate of LNG was estimated to be 95% when taken within 24 hours, decreasing to 58% when taken between 49 and 72 hours after intercourse. The effectiveness of LNG also decreases as body mass index (BMI) increases. In one study, there was a four-fold risk of pregnancy among obese women, as compared to those women who had a BMI within the normal range. The most common side effects with LNG include nausea and vomiting, and menstrual cycle disruption.
If you are in need of emergency contraception, visit your local pharmacy, consult your doctor, or go to the nearest emergency unit at your local hospital.
To read an article about emergency contraception, click here.
To read more about “Plan B” (Levonorgestrel), click here.