PIP: Women throughout the world and throughout time have ingested substances such as mercury, diluted copper ore, and various noxious solutions in the mistaken belief that these substances would prevent pregnancy. The era of modern contraception began in 1937 with the discovery that the administration of progesterone could halt ovulation in rabbits. During the next decade, work proceeded on finding an easy and less expensive way to synthesize progesterone and to develop the synthetic estrogens mestranol and ethinyl estradiol. Initial trials in humans proved that these hormones could prevent ovulation. In 1950, with support from Margaret Sanger and Katharine Dexter McCormick, Gregory Goodwin Pincus developed the first oral contraceptive (OC), which consisted of supplemental progestin and 0.5 mg norethindrone. In the early 1990s, the Ortho Pharmaceutical Corporation introduced an OC that combined the synthetic progesterone norgestimate and 35 mcg of ethinyl estradiol. By 1988, several noncontracepting health benefits of the OC were recognized, including decreased rates of ovarian cancer, endometrial cancer, pelvic inflammatory disease, ovarian cysts, benign breast disease, iron deficiency anemia, and dysmenorrhea. These health benefits outweigh risks even in nonsmoking women over 40. In the US, 80% of women have used the OC at one time, and they are using this most popular form of reversible contraception longer than ever.