postcoital contraception


Also found in: Dictionary, Thesaurus, Legal, Encyclopedia.

morning-after pill (MAP),

an oral drug that, when taken by a woman within 2-3 days after intercourse, reduces the probability that she will become pregnant.

The U.S. Food and Drug Administration (FDA) has approved two regimens for postcoital contraception. The Yuzpe regimen consists of a combination of progestogen (levonorgestrol 0.25 mg or norgestrel 0.5 mg) and estrogen (ethinyl estradiol 100 mcg) taken at once and repeated in 12 hours. Alternatively, two doses of levonorgestrel 0.75 mg may be taken without estrogen. With either regimen, the first dose should preferably be taken within 24 hours after intercourse, and not more than 72 hours after. The Yuzpe method reduces the likelihood of pregnancy by about 57%, the levonorgestrel method by 85%. About 50% of women experience uterine bleeding within 1 week and most of the rest within 3 weeks unless conception has occurred. If taken early enough, the hormones may prevent fertilization by altering tubal function or exerting toxicity against the ovum. Probably, however, they usually act by preventing implantation of a fertilized ovum. This is not emergency contraception but rather chemical abortion. The incidence of nausea is about 40% with levonorgestrel alone and about 65% with the Yuzpe regimen. Headache, fluid retention, and breast tenderness may also occur. This procedure is contraindicated in women for whom oral contraceptives are contraindicated, such as those with hypertension or a history of stroke or thromboembolic disease. The short course of high-dose hormones probably does not interrupt a pregnancy after implantation has occurred, and there is no evidence that fetal harm has occurred when such a pregnancy has continued to term. However, hormone use is contraindicated in known pregnancy or if the woman has had unprotected intercourse within the preceding 3-10 days. An application for over-the-counter marketing of levonorgestrel has been denied by the FDA.

morn·ing af·ter pill

(mōr'ning af'tĕr pil)
An oral medication, consisting of two pills taken 12 hours apart that, when taken by a woman within 2-3 days after intercourse, reduces the probability that she will become pregnant.
Synonym(s): emergency contraceptive, emergency hormonal contraception, postcoital contraception.

postcoital contraception

The use of any measure to prevent pregnancy after sexual intercourse has occurred. Such measures are not strictly contraceptive as they are likely to act after conception has occurred. They include taking two high-dose contraceptive pills as soon as possible and then 12 hours later; the taking of a single dose of mifepristone; and the insertion of a copper-releasing IUCD. Mifepristone is currently not licensed anywhere outside China for postcoital contraception. Also known as emergency contraception or the ‘morning after pill’.

postcoital contraception,

n various contraceptive methods used by women to prevent pregnancy after unprotected sex. Examples include hormone-based treatments, RU-486 (a synthetic steroid), and copper IUDs. Also called
emergency postcoital contraception or
morning-after pills.
References in periodicals archive ?
As noted previously, the levonorgestrel regimen has been studied as an ongoing or primary method of postcoital contraception.
Side Effects of Danazol Compared with an Ethinyloestradiol/Norgestrel Combination When Used for Postcoital Contraception," Contraception, 27:39-49, 1983.
Molla, "Hormonal Postcoital Contraception with an Ethinylestradiol-Norgestrel Combination and Two Danazol Regimes," European Journal of Obstetrics & Gynecology and Reproductive Biology, 37:253-260, 1990; A.
Nolan, "Six Years of Clinical Experience Using Postcoital Contraception in College Women," Journal of American College Health, 42:61-63, 1993.
Mochtar, "Het risico van een onbedoelde zwangerschap na een onbeschermde coitus; beschouwing bij de huidige hormonale postcoitale anticonceptiemethoden" (The Risk of Unintended Pregnancy After a Single Unprotected Intercourse: Reflection on the Current Postcoital Contraception Methods), Ned Tijdschr Geneeskd, 136:2159-2161, 1992.
Rowlands et al, "Side Effects of Danazol Compared with an Ethinylestradiol/Norgestrel Combination when Used for Postcoital Contraception," Contraception, 27:39-49, 1983.
Elstein, "Comparison of Yuzpe Regimen, Danazol and Mifepristone (RU486) in Oral Postcoital Contraception," British Medical Journal, 305:927-931, 1992.
Postcoital contraception with diethylstilbestrol: Updated.
F Colombo and R Molla, "Hormonal Postcoital Contraception with an Ethinylestradiol-Norgestrel Combination and Two Danazol Regimes," European Journal of Obstetrics & Gynecology and Reproductive Biology, 37:253-260,1990; A.
Haspels, "Overall View of Postcoital Contraception," Advances in Contraception, 8:214, 1992.
Elstein, "Comparison of Yuzpe Regimen, Danazol, and Mifepristone (RU 486) in Oral Postcoital Contraception," British Medical Journal, 305:927, 1992.
Howie, "Potential Use of Postcoital Contraception to Prevent Unwanted Pregnancy," British Medical Journal, 290:1040,1985.