Clinical evaluation of an oral progestin contraceptive, R-2323, 5mg, administered at weekly intervals

Abstract

A new contraceptive compound, R-2323, was tried as a "weekly pill". The pregnancy rate at 12 months was 3.7 considering only method failures. The most important ill effect was alterations in bleeding patterns, with a predominance of cycle irregularity. Oligomenorrhea was present in 58% of the cycles after 6 months of use, and this symptom was responsible for a discontinuation rate of 10 percent at the end of a year. Polymenorrhea and intermenstrual bleeding were less frequent and caused a discontinuation rate of 6 percent in a year of use. Chloasma, acne and hirsutism increased in frequency with time of use, and even though these problems affected relatively few patients, almost all of those with these problems discontinued. These three symptoms together caused almost as many discontinuations as excessive bleeding. Endometrial biopsies taken during treatment showed both proliferative and secretory endometria in the group receiving 2.5 mg a week and were predominantly proliferative in t