Unexpected pregnancy during hormone-replacement therapy in a woman with elevated follicle-stimulating hormone levels and amenorrhea.

Pregnancy in patients with hypergonadotropic amenorrhea, although previously reported, remains quite rare. Women may conceive spontaneously or following different regimens of ovulation induction, thus indicating that ovarian failure is not always permanent. The case of an 18-year-old woman with premature ovarian failure, who conceived during hormone-replacement therapy, is reported. During hormone-replacement therapy, elevated gonadotropin levels returned to the physiologically normal range. It is suggested that this restored the receptors to luteinizing hormone and to follicle-stimulating hormone, which might have been downregulated. This hypothesis is supported by previous results from clinical trials and experimental work on a rat model.