Endocrinologic characteristics of partial ovarian failure.

Three young women with primary ovarian failure, secondary amenorrhea or oligo-ovulation, and normal gonadotropin levels are reported on here. Vaginal cytology and serum estradiol levels indicated the two women to be persistently hypoestrogenic. The third case, who had the Turner phenotype, was hypoestrogenic during anovulatory cycles but occasionally ovulated. Basal serum LH and FSH were normal. All were tested with synthetic LH-releasing hormone and had a brisk response, LH levels rising 51-198 ng/ml above baseline and FSH rising 278-536 ng/ml. Plasma levels of testosterone, dehydroepiandrosterone sulfate, and progesterone were normal. Gonadal dysgenesis was suggested in two on the basis of an abnormal karyotype, and isochromosome of the short arm of X in Case 2, and an isochromosome of the long arm of X in Case 3. The diagnosis of primary hypogonadism was established by laparoscopy and ovarian biopsy. The latter studies revealed small ovaries with a scarcity of primordial and primary follicles, yet with evidence of current or previous follicular activity. The observation that hypoestrogenism was so marked in two of our patients that elevated serum FSH would have been expected, suggests that the presence of a limited number of ovarian follicles suffices to prevent hypergonagotropism in hypoestrogenic women by a mechanism which does not involve elaboration of sex steroids.