[Effect of norethisterone acetate on ovarian functional activity]

Nine women were examined for a period of the 13th to 15th day of the menstrual cycle before and during norethisterone acetate use (10 mg within 10 days). Two-phase character of hormone secretion persisted in 6 of 9 cycles during norethisterone acetate administration. The changed hormone concentration in the 2nd phase and the shortened period of luteinizing hormone functional activity were seen in each cycle. Large individual differences were observed in the blood plasma norethisterone content. No correlation between norethisterone level and the ovarian response pattern was found.