PIP: 990 women, 18-35 years of age, underwent subcutaneous silastic implants of levonorgestrel (N = 492) and norgestrionone (N = 498). These patients were compared to 402 women who used the Copper-T 200 IUD. Control examinations were performed 1,3,6,9, and 12 months after contraceptive use began. There were 3 pregnancies in the levo-norgestrel group which occurred during the first 4 months of contraceptive use. There were 17 pregnancies in the norgestrionone group, which occurred toward the end of the contraceptive use period. Menstrual bleeding disorders were the most frequent reasons for discontinuing subcutaneous implant use and occurred more often among the levo-norgestrel patients (generally metrorrhagia and menorrhagia). There were 4 pregnancies among the IUD patients. The continuation rate for the levo-norgestrel group was 74.6%; for the norgestrionone users 79.9%; and for the IUD users 81.1%. Anemia and changes in blood pressure were not observed among the subcutaneous implant patients. IUD patients showed no weight gain, while the subcutaneous implant patients gained on an average 1 kg.