Emergency Contraceptive Pills: A Simple Proposal to Reduce Unintended Pregnancies. (VIEWPOINT).

About 3.5 million unintended pregnancies occur each year in the United States; roughly half (1.7 million) of these result from contraceptive failure. (1*) We argue here that the considerable human costs resulting from this very large number of unintended pregnancies could be reduced significantly--at modest cost--by more widespread distribution of postcoital hormonal contraceptives. Although this therapy is commonly called morning-after treatment, we prefer to use the label emergency contraceptive pills (ECPs) to avoid the incorrect implication that the treatment must be delayed until the morning following unprotected intercourse. (2)

Two simple postcoital hormonal regimens are available. The "Yuzpe" method (3) involves taking four combined estrogen/progestin pills, each containing 50 mcg of ethinyl estradiol and 0.5 mg of dlnorgestrel (marketed in the United States as the oral contraceptive Ovral). This regimen has replaced the older postcoital therapy involving high doses of the estrogen diethylstilbestrol, primarily because the regimen using the combined pill has fewer side effects. Two tablets are taken within 72 hours after unprotected coitus (preferably as soon as possible), and two more are taken 12 hours later. The total regimen is 200 mcg of ethinyl estradiol and 2.0 mg of dl-norgestrel.

A newer postcoital therapy consists of three 200-mg tablets of danocrine (marketed in the United States as Danazol) taken within 72 hours of unprotected intercourse and repeated 12 hours later. Danocrine, a synthetic steroid used in the treatment of endometriosis, has a lower incidence of nausea, vomiting and breast tenderness than the combined-pill regimen when used as a postcoital contraceptive. (4)

Postcoital hormonal treatment appears to prevent pregnancy by temporarily disrupting a woman's hormonal patterns. ECPs alter the release of hormones from the ovaries, disturb the development of the uterine lining and disrupt the transport of the fertilized ovum through the fallopian tubes. (5)

The Efficacy of ECPs

Although ECPs are certainly not 100% effective, they do provide considerable protection against accidental pregnancy. A recent article in The Lancet - "Postcoital Contraception: Myth or Realty?" -- has undoubtedly created some confusion among clinicians. (6) The authors reanalyzed data from 10 clinical studies that had examined the efficacy of ECPs. Using two separate methods to estimate the number of pregnancies that would have occurred without the use of ECPs, they produced effectiveness rates for ECPs that ranged either from 0% to 96% or from 56% to 94%. Our scrutiny of the same evidence, presented elsewhere in this issue (see page 262), leads us to dismiss unequivocally any suggestion that combined ECPs are ineffective. (7) According to our analysis, use of combined ECPs would reduce the expected number of pregnancies (or, alternatively, the expected risk of pregnancy) by more than 75%. Results concerning the efficacy of danocrine are mixed. In one trial in which women were randomly assigned to use either danocrine (a total of only 800 mg, given in two doses) or combined ECPs, danocrine proved to be somewhat more effective, although the difference in efficacy was not significant. (8) The investigators also studied a regimen consisting of 1,200 mg of danocrine given in three doses (three 400-mg doses taken at 12-hour intervals) and concluded that the 1,200-mg danocrine regimen was the most effective of the three. However, the investigators in a second trial concluded, after an interim analysis of their results, that the efficacy of danocrine was so slight that they could not ethically continue the study. (9)

The Potential for Use