Patent ID: 8461138

Claim:
A method of contraception comprising the steps of sequentially administering to a female of child bearing age: (a) a composition I containing a progestogen in an amount equivalent to about 0.3 to about 1.5 mg norethindrone acetate and about 2 to about 9 mcg of ethinyl estradiol for about 5 to about 9 days, wherein composition I is the first composition used by the female of child bearing age in the method of contraception; (b) a composition II containing a progestogen in an amount equivalent to about 0.3 to about 1.5 mg of norethindrone acetate and about 10 to about 50 mcg of ethinyl estradiol for about 5 to about 9 days; (c) a composition III containing a progestogen in an amount equivalent to about 0.3 to about 1.5 mg of norethindrone acetate and about 10 to about 50 mcg of ethinyl estradiol for about 8 to about 12 days; and (d) a composition IV substantially free of a progestogen and containing about 2 to about 9 mcg of ethinyl estradiol for about 2 to about 6 days, wherein the amount of ethinyl estradiol in composition III is greater than the amount of ethinyl estradiol in composition II by at least 5 mcg of ethinyl estradiol, the progestogen in composition I, II, and III is norethindrone acetate or norethinedrone and the sequential administration of compositions I, II, III and IV is repeated after the completion of the administration of composition IV.