Several other brands of combined oral contraceptives contain the same hormones needed for the Yuzpe method, but in lower doses.
Efficacy studies of the Yuzpe method have yielded greatly varying results, in part because the definition of efficacy is slightly different for a postcoital method than for a conventional method.
* Comment: Studies have found that the levonorgestrel-only method reduces the pregnancy rate after unprotected intercourse by nearly 90%, compared with about 75% with the Yuzpe method
. The former is possibly more effective because it causes less nausea, and women are more likely to take the second dose, said Dr.
Each two-pill dose contains 100 [micro]g of ethinyl estradiol and 0.50 mg of levonorgestrel, the regimen used in the Yuzpe method
(17) Women found danazol more acceptable than the Yuzpe method
because it caused fewer, milder side effects of shorter duration.
The purpose of this article is to examine rigorously the efficacy of one method of emergency contraception: the Yuzpe method. The Yuzpe regimen has replaced the older postcoital therapy of high doses of the estrogen diethylstilbestrol, primarily because the Yuzpe regimen has fewer side effects.
Investigators have often evaluated the efficacy of the Yuzpe method by calculating its failure rate (pregnancies divided by the number of women treated), which we consider an inappropriate measure.