EmergencyContraception
Background
Emergency contraceptives are used to prevent pregnancy after unprotected intercourse. Most commonly known as "the morning after pill," emergency contraceptive pills are hormones that are consumed by women after engaging in unprotected sex. Modern day emergency contraceptive use dates back to the 1970's.
Types of Emergency Contraceptives
There are two types of emergency contraceptive pills available.
- levonorgestrel - most effective within 72 hours or 3 days after unprotected sex, but has been known to be effective up to 120 hours or 5 days. These pills are available over the counter in several countries including Canada, and by perception in several others. Progestin pills are available in either a single dose or two pill dose, taken 12 hours apart.
- antiprogestin ulipristal acetate - effective within 120 hours or 5 days after unprotected sex. These pills are available by prescription in over 50 countries.
Additionally, intrauterine devices have been used as emergency contraceptives, but are mainly used as a primary contraceptive. IUDs contain either copper or hormonal levonorgestrel to prevent pregnancy. When inserted as an emergency contraceptive, both IUDs can be effective up to 5 days post intercourse.
How it Works
Levonorgestrel pills are manufactured hormones that, when given in a high enough dosage, prevent pregnancy. It works by delaying ovulation or the release of an egg within the ovaries, preventing fertilization, or preventing a fertilized egg from attaching to the uterus. Levonorgestrel pills will not terminate a pregnancy or destroy a fertilized egg after it has attached to the uterus. Antiprogestin ulipristal acetate pills are a form of hormone antagonist which works to block hormone receptors, specifically progestogen, which is a sex hormone that effects pregnancy. Intrauterine devices are T-shaped devices that prevent sperm from actively reaching the egg. Copper IUDs work to damage and disrupt sperm in order to prevent its ability to attach to uterine lining. Hormonal IUDs release a small amount of levonorgestrel which has a fatal effect on sperm.
Effectiveness
Approximately 1 or 2 in every 100 women who take emergency contraceptives will still get pregnant [1]. Levonorgestrel pills have an 89% effectiveness in preventing pregnancy, but its effectiveness reduces as more time passes. Antiprogestin pills are 85% effective, but its effectiveness remains the same within the 5 day period [2]. These pills will only work after unprotected sex has happened, but will not work to prevent future pregnancies. Levonorgestrel pills may be less effective for women who are over weight, in which case an antiprogestin pill would be more appropriate. Additionally, taking more than one pill does not increase its efficacy.
IUDs are the most effective form of emergency contraceptive, with a rate of 99%. However, these devices must be inserted by a doctor or health care professional. They are less easily accessible because of this, and tend to run a higher cost. IUDs provide protection from pregnancy for up to 12 years.
Possible Side Effects
Women have been known to experience side effects after consuming the morning after pill. For levonorgestrel users, the most common side effects are nausea, abdominal pain, fatigue, headache, dizziness, breast tenderness, vomiting, diarrhea and irregular menstrual bleeding [3]. Antiprogestin users may experience headaches, stomach pain, nausea, menstrual pain, tiredness, and dizziness[4].Side effects of the copper IUD can include mild to moderate pain upon insertion, cramping or backaches after insertion, spotting between periods, heavier periods and worse menstrual cramps [5].
Brands
Levonorgestrel brands available in Canada include [6]:
- Plan B
- Norlevo
- Option 2
- Next Choice
By perception in Canada, the antiprogestin pills available are:
- EllaNow
Most emergency contraceptive pills cost anywhere between $10 and $80, but may be applicable for coverage through health insurance plans[7]. IUDs can cost anywhere from 0$-$900, depending on healthcare plans and who is inserting the device.