Occurrence of ovulation in women receiving the injectable contraceptive norethisterone oenanthate.

Ovarian function was studied in ten women receiving a single intramuscular injection of 200 mg norethisterone oenanthate. Two of the ten women appeared to ovulate within 60 days of injection and a further four within 90 days. Follicular activity probably not followed by ovulation occurred in five subjects within 60 days of the injection and in a further subject within 90 days. Only one subject showed no evidence of follicular or luteal activity during the course of this study. There was wide variation in the rate at which the administered gestagen was metabolised and no correlation between the rate of metabolism of norethisterone and the return of ovarian function or the ponderal index, height or weight of the subjects.