Abstract: Disclosed is an oral contraceptive regimen containing daily dosage units each containing from 70 to 80 micrograms of desogestrel, 3-ketodesogestrel or mixtures thereof. It has been found that by making a selection of desogestrel or 3-ketodesogestrel at the described dosages in an oral contraceptive regimen administered over the entire menstrual cycle (e.g. 28 days), effective ovulation inhibition is achieved and intermenstrual bleeding is avoided, while acceptable cycle control is retained. Moreover, the regimen also prevents the formation of persistent ovarian cysts.

Abstract: A contraceptive method and regimen utilizing an initially greater amount of progestogen, which gradually tapers over the period in which the contraceptive is administered. The regimen includes a multiphasic combination and contraceptive kit containing at least 21 daily sequential dosage units divided into 3 phases. The first phase contains 6-8 dosage units, each containing a progestogen at a dosage equivalent in progestogenic activity to 75-150 .mu.g desogestrel and an estrogen at a dosage equivalent in estrogenic activity to 20-25 .mu.g ethinyl estradiol. The second phase contains 6-8 dosage units, each containing less progestogen than in the previous dosage units, but still having progestogen equivalent to 75-125 .mu.g desogestrel and an estrogen equivalent to 20 .mu.g ethinyl estradiol. The third phase contains 6-8 dosage units, each containing less progestogen than in the previous dosage units, but still containing a progestogen equivalent to 75-100 g desogestrel and an estrogen equivalent to 20 .mu.