A method of contraception that provides for sequentially administering to
a female of child bearing age: (a) a first composition containing a
progestin in an amount equivalent to about 0.3 to about 1.5 mg
norethindrone acetate and an estrogen in an amount equivalent to about 5
to about 20 mcg of ethinyl estradiol for about 22 to about 26 days; (b) a
second composition containing an estrogen in an amount equivalent to
about 5 to about 20 mcg of ethinyl estradiol for about 2 to about 3 days
and an optional third composition that is a placebo provided that (i) if
estrogen administration is continuous then the first composition is
administered for 25 to 26 days, the second composition is administered
for 2 to 3 days and no third composition is administered and (ii) if
estrogen administration is not continuous then the first composition is
administered for 22 to 24 days, the second composition is administered
for 2 to 3 days and the third composition is administered for 1 to 4
days. The total cycle length is 28 days, with the first composition
administered on day 1 of the menstrual cycle, defined as the first day of
menstrual bleeding, or on the first Sunday after the first day of the
menstrual cycle.