Emergency contraception (EC) refers to contraceptive measures that are taken after sex to prevent pregnancy.

The various forms of EC include:

1) Emergency contraceptive pills (ECPs): Drugs that act both to prevent ovulation or fertilization and post-fertilization implantation of an embryo.
2) Intrauterine devices (IUDs)

Since Emergency Contraceptive methods act before implantation, they are medically and legally accepted forms of contraception.

The Emergency contraceptive pills contains higher doses of the hormones i.e. estrogens, progestin, or both. These are taken after unprotected sexual inter course to prevent pregnancy. Mifepristone is also used as EC. It is an anti-hormonal drug, and does not contain estrogen or progestin. ECP’s are effective when used shortly before intercourse, and are licensed for use up to 72 hours after sexual intercourse.

Types of Emergency Contraceptive Pills’s

Progestin-only EC : The progestin-only method uses the progestin levonorgestrel in a dose of 1.5 mg. Progestin-only EC is available as an emergency contraceptive worldwide, and is also known as Plan B, Levonelle, Escapelle, NorLevo, and Postinor-2. This pill works up to 72 hours after intercourse.

The combined or Yuzpe regimen uses large doses of both estrogen and progestin, taken as two doses at a 12-hour interval.

The drug mifepristone is also used either as an ECP or an abortifacient, depending upon whether it is used before or after implantation. As an Emergency Contraception, a low dose of mifepristone is less effective than higher doses, but has some side effects. Higher doses of mifepristone can disrupt implantation and prevent pregnancy.

Ulipristal acetate or Ellaone is a drug similar to mifepristone and is also approved as an ECP. It works up to 120 hours after intercourse.

According to the International Federation of Gynecology and Obstetrics, “EC is not an abortifacient because it has its effect prior to the earliest time of implantation.” Since ECPs act before implantation, they are medically and legally accepted forms of contraception. The most common side effect reported by emergency contraceptive pills is nausea. Other common side effects include abdominal pain, fatigue, headache, dizziness, temporary disruption of menstrual cycle and breast tenderness.