One hundred twenty women completed 901 woman-months of birth control with a new triphasic oral contraceptive. No pregnancies occurred, and good cycle control was achieved. Spotting and breakthrough bleeding were minimal, and amenorrhea did not occur. Changes in body weight and blood pressure were not statistically significant. The triphasic compound was well tolerated. Headache and dizziness were frequent complaints during the initial cycles but tended to subside within a few months.