women s health issues
Emergency Contraception
Introduction
Emergency contraception may be used to prevent pregnancy for a short period of time after unprotected sex. Emergency contraception decreases the chance of pregnancy after one episode of unprotected intercourse, including when the act occurs near the time the egg is released (ovulation)—when conception is most likely. Overall, the chance of pregnancy is about 5% after one episode of unprotected sex, but closer to ovulation, it is about 20 to 30%. The sooner emergency contraception is used, the more likely it is to be effective. Intrauterine Devices (IUDs) is the most effective form of emergency contraception. The Insertion of acopperIUD:To be effective, the IUD must be inserted within 5 days of unprotected sex or, if the time of ovulation can be estimated, within 5 days of ovulation (release of an egg from the ovary). The chance of pregnancy after insertion of the IUD is 0.1%—the same as it is when the IUD is used for regular birth control. Also, after its insertion, the IUD can be left in place to provide continued contraception for up to 10 years. The effectiveness of acopperIUD as emergency contraception is not affected by weight. Thus, in women who are obese who strongly desire to avoid pregnancy, thecopperIUD is the preferred method for emergency contraception. Insertion of a high-doselevonorgestrel-releasing IUD:To be effective, this IUD should be inserted within 5 days of unprotected sex or, if the time of ovulation can be estimated, within 5 days of ovulation. The chance for pregnancy after insertion of this IUD is 0.3%. Ulipristalacetate:One dose of this medication is taken. It is more effective thanlevonorgestrel. It must be taken within 5 days (120 hours) after unprotected intercourse. The chance of pregnancy is about 1.5%.Ulipristalacetate is more effective thanlevonorgestrelfor women who are obese, but having obesity decreases its effectiveness. A prescription is needed. After women takeulipristalacetate, they must wait 6 days before using a hormonal contraceptive that contains a progestin. They should use a backup method of contraception (such as a condom) for 7 days after starting to use the hormonal contraceptive. Levonorgestreltaken by mouth:Levonorgestrelis most commonly used. It is a progestin often taken in lower doses for contraception. Women may take a dose, followed by another dose 12 hours later. Or they may take one higher dose. The chance of pregnancy is about 2 to 3%. However,levonorgestrelemergency contraception may be less effective in women who are obese. The dose is more effective the sooner it is taken. It must be taken within 5 days (120 hours) after unprotected intercourse (although it is less effective if taken after 3 days). In the United States, these pills are available over-the-counter without restriction for women of all ages who have had unprotected intercourse. A hormonal contraceptive may be started at the same time. A backup method (such as a condom) is recommended for 7 days after starting to use the hormonal contraceptive. Yuzpe method:For this method, a combination oral contraceptive—ethinyl estradiol(a form of estrogen) pluslevonorgestrel—is used, but it is slightly less effective thanlevonorgestrelorulipristalacetate. Two combination pills are taken, followed by two more pills 12 hours later but taken within 72 hours of unprotected sex. A high dose ofestrogenis used. The high dose often causes nausea and sometimes causes vomiting. Doctors may recommend medications that can help prevent nausea and vomiting. This method is less effective than other methods and is used only when women do not have access to other methods. A hormonal contraceptive may be started at the same time. A backup method (such as a condom) is recommended for 7 days after starting to use the hormonal contraceptive. A pregnancy test is done 2 to 3 weeks after emergency contraception is used to make sure the woman is not pregnant. Resumption of menstrual periods and a negative pregnancy test result confirms that the woman is not pregnant. 