3-month contraceptive injection approved.

FDA has approved medroxyprogesterone acetate as Depo Provera Contraceptive Injection, effective for 3 months in preventing pregnancy in women. In clinical studies, the drug's failure rate was less than 1%. However, physicians must ensure that patients receive injections on schedule to prevent pregnancy. The recommended dose is 150 mg administered every 3 months by deep, intramuscular injection in the gluteal or deltoid muscle. Most women in clinical studies of Depo Provera experienced menstrual irregularities. As use continued, amenorrhea became common, reported by 57% of the women by the end of a year of treatment. Other side effects included weight gain, headache, nervousness, abdominal pain or discomfort, dizziness, and asthenia. Physicians should administer the drug only to women found not to be pregnant, because fetal exposure may lead to low birth weight and other problems. Recent data have demonstrated that longterm use may contribute to osteoporosis, and the drug's manufacturer, the Upjohn Company of Kalamazoo, Michigan, will conduct additional research to study this possible side effect. Contraindications are similar to those for other contraceptives and include undiagnosed vaginal bleeding, known or suspected malignancy of breast, thromboembolic disorders, cerebral vascular disease, and liver dysfunction. Depo Provera was developed in the 1960s and has been approved for contraception in many other countries. When FDA first reviewed data on the drug in the 1970s, animal studies raised questions about its potential to cause breast cancer. Since then, longterm controlled clinical studies in other countries have shown a risk of breast cancer comparable to oral contraceptives, and no increased risk for ovarian, liver, or cervical cancer. The studies also showed that the contraceptive injection reduced the risk of endometrial cancer. FDA approved the drug October 29, 1992.