Morphological and functional features in human fetal testicles during prenatal hypoxia

Introduction. Intrauterine hypoxia is one of the most frequent complications in pregnancy. It is one of the risk factors of fetal development disorders. In the antenatal period, the effects of hypoxia on re-productive system can impair fetus development and lead to negative consequences. The aim was to studypathological and functional features of testes development in different periods of gestation with chronic intrauterine hypoxia. Materials and methods. We examined autopsies of testicular tissues of 78 fetuses deceased at gestation weeks 19–40. Histological and immunohistochemical methods (using antibodies to Ki-67, Bcl 2, AR, ER, and FGF) were employed. Results. Morphometric examination showed a decrease in the number of tubules, cells in the tubules, and the area of the tubules with a significant increase in the stromal area. Immunohistochemistry revealed a weak expression of proliferation and apoptosis marker, a pronounced diffuse expression of estrogen receptor, and a weak expression of androgen receptor. Fibroblast growth factor expression was increasing up to week 29 and then sharply decreased. Conclusion. Chronic hypoxia leads to damage of germ cells and gland atrophy in the testicles of fetuses. Prolonged oxygen deprivation in the testicular tissue triggers compensatory mechanisms, which manifest in the apoptosis inhibitor expression. Hypoxia disrupts proliferation processes and reduces the functional activity of interstitial endocrinocytes, which is confirmed by the weak AR expression and pronounced ER expression during all gestation periods. These structural changes in testicular morphogenesis may lead to impaired fertility. Keywords: hypoxia, testicle, immunohistochemistry, fertility disorders, antenatal period