The FDA has approved drospirenone, 3.0 mg, and ethinyl estradiol, 0.030 mg (Yasmin 28 tablets; Berlex Laboratories, Wayne, NJ), an oral contraceptive, for prevention of pregnancy. The drug was approved on the basis of results of clinical studies of up to 2 years' duration, in which 2629 women completed 33 160 cycles of Yasmin use without any other contraception. Their mean (SD) age was 25.5 (4.7) years, and the pregnancy rates in these studies were less than 1 per 100 person-years of use.
Schwetz BA. New Oral Contraceptive. JAMA. 2001;286(5):527. doi:10.1001/jama.286.5.527