Serum gonadotropin responses to estrogen and progestogen in recently castrated human females

Serum FSH and LH levels were studied in 3 females recently oophorectomized while in the reproductive age and the responses of FSH and LH levels to exogenous estrogen (mestranol, 0.1 mg) and progestogen (ethynodiol diacetate, 2.0 mg) administered separately and in combination were investigated. Medication was withheld until the 41st to 53rd postoperative days. Mestranol was then given daily for 14 days and stopped; after 14 unmedicated days ethynodiol diacetate was administered for 14 days; after a 2nd 14-day hiatus, both drugs were given for 14 days. Bloods were drawn preoperatively and immediately postoperatively, on alternate days during the first or second week before receiving mestranol, on alternate days during the week preceding each other treatment, and 3 times a week during each medicated interval. LH and FSH were measured by a double antibody radioimmunoassay. FSH and LH rose promptly in 2 subjects the first week after surgery and rose in all 3 patients over the ensuing 5 weeks. During estrogen administration, FSH levels declined and LH initially declined and then increased. With the progestogen no consistent change was seen in LH or FSH. With estrogen and progestogen administered in combination, FSH fell gradually and LH declined progressively.