Serum and intratesticular inhibin B, AMH, and spermatogonial numbers in trans women at gender-confirming surgery: An observational study.

Abstract

Anti-Müllerian hormone and inhibin B are produced by Sertoli cells. Anti-Müllerian hormone secretion indicates an immature Sertoli cell state. Inhibin B serves as a marker of male fertility. Identification of markers reflecting the presence of germ cells is of particular relevance in trans persons undergoing gender-affirming hormone therapy in order to offer individualized fertility preservation methods. Serum and intratesticular inhibin B and anti-Müllerian hormone values were assessed and related to clinical features, laboratory values, and germ cell numbers. Twenty-two trans women from three clinics were included. As gender-affirming hormone therapy, 10-12.5mg of cyproterone acetate plus estrogens were administered. Height, weight, age, medication, and treatment duration were inquired by questionnaires. Serum luteinizing hormone, follicle-stimulating hormone, testosterone, and estradiol were measured by immuno-assays. Serum and intratesticular inhibin B and anti-Müllerian hormone were measured by commercially available ELISAs. Spermatogonia were quantified as spermatogonia per cubic millimeter testicular tissue applying a morphometric analysis of two independent testicular cross-sections per individual after MAGEA4 immunostaining. Patients with high inhibin B levels presented with a higher number of spermatogonia (*p<0.05). Furthermore, mean serum inhibin B was associated with low age (*p<0.05), low follicle-stimulating hormone (*p<0.05), and low testosterone (*p<0.05). Serum anti-Müllerian hormone, however, was not related to spermatogonial numbers. It correlated with high testosterone (*p<0.05) and high follicle-stimulating hormone (*p<0.05) only. High intratesticular inhibin B was accompanied by high luteinizing hormone (*p<0.05), high follicle-stimulating hormone (**p<0.01), and high testosterone levels (**p<0.01). Higher the intratesticular anti-Müllerian hormone levels, the longer gender-affirming hormone therapy was administered (*p<0.05). Serum inhibin B levels indicate the presence of spermatogonia, whereas anti-Müllerian hormone seems not to be a reliable marker concerning germ cell abundance.