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Updated: Aug 13, 2026

Exploring Independent Effects of Follicle-Stimulating Hormone In Vivo in a Mouse Model
Published on: August 11, 2023
Norethindrone inhibition of testosterone secretion by an ovarian Sertoli-Leydig cell tumor
Abstract:
A woman with severe hyperandrogenemia and virilization was found to have a fall in serum testosterone (T) concentration while taking an oral contraceptive containing norethindrone (500 vs. 164 ng/dL). Subsequent surgical exploration revealed an ovarian Sertoli-Leydig cell tumor. In vitro, the tumor secreted T (mean, 1.88 ng/mg X 4 h). hCG did not stimulate T secretion. In addition, norethindrone inhibited T secretion (0.33 ng/mg X 4 h). We conclude that norethindrone directly suppressed T production by the Sertoli-Leydig cell tumor.
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