The Journal of Clinical Endocrinology & Metabolism · 1973 · 166 citations · 0 references
SpermatogenesisFertilityComparative EndocrinologyReproductive HealthFemale Reproductive FunctionCm Cr-lengthReproductive BiologyEmbryologyReproductive EndocrinologyHuman Sexual DevelopmentReproductive MedicineEstradiol ConcentrationsPublic HealthDisorders Of Sex DevelopmentSteroid MetabolismSexual And Reproductive HealthReproductive HormoneDevelopmental EndocrinologyI. Fetal GonadalEndocrinologyPlacental FunctionSexual Development (Clinical Endocrinology)Developmental BiologyAdrenal HealthPhysiologyMedicineIsotope-displacement AssaysEndocrine ResearchSexual Development (Developmental Psychology)
Testosterone and estradiol were quantified by isotope‑displacement assays in gonads and adrenals of 54 human fetuses (33 male, 21 female) and correlated with crown‑rump length (5–24 cm, 10–25 weeks). Testosterone was abundant in testes (≈1400 pg/mg) but negligible in ovaries and adrenals, peaking at 7–10 cm CR and declining thereafter, while estradiol was undetectable; these patterns indicate heightened androgen production during male genital differentiation.
Testosterone and estradiol concentrations were measured by isotope-displacement assays in the gonads and adrenals of 54 human fetuses (33 male, 21 female) delivered by hysterotomy. Results were correlated with crownrump (CR) length which ranged from 5 to 24 cm, corresponding to 10–25 weeks fetal age. Testosterone concentration averaged 1400 pg/mg in the testes but was negligible (<90 pg/mg) in the ovaries and in the adrenals of both sexes. Testosterone was found in appreciable amounts in the testes from the youngest specimens, reached a peak at 7–10 cm CR-length and declined by 13–14 cm CR-length. Little or no estradiol was detected in fetal testes, ovaries and adrenals and there were no sex differences in these levels. These data provide evidence that human fetal testicular tissue accumulates testosterone in a pattern suggesting higher androgen production at the time of male genital differentiation.