Tabriz University of Medical Sciences Medical Journal of Tabriz University of Medical Sciences 2783-2031 38 1 2016 04 05 The Effects of Prenatal Dexamethasone on Development and Function of Testis in Offspring of Rats of First Lineage 26 31 EN Seyed Ebrahim Hosseini Maryam Moshveghi Journal Article 2016 04 26 Background & Objectives: Dexamethsone is one of the widely used glococorticoids that prescribe in many situations such as pregnancies that are prone to preterm delivery, so this study was conducted to investigate the effect of prenatal dexamethasone administration on the function of pituitary-gonadal axis and secretary function of testis of offspring of rats. Material and Methods: In this study, 40 pregnant rats were divided into control group, sham group, and 3 experimental groups that receiving 0.5, 1, and 2 mg/kg doses of dexamethasone administered from the eighth day until the end of pregnancy Quaqu on day (QOD). After delivery, neonates and mothers received no treatment and after puberty, sampling from the heart and testis of male children was done, then plasma levels of testosterone,FSH, LH and the number of spermatogony, spermatocyte, spermatid, sertoli and leydig cells were determined. Results were analysed with the SPSS-20 and ANOVA and Duncan test (p≤0.5). Results: Results of this study revealed that, dexamethson administration leads to increase of FSH and, LH levels and decrease of testosterone levels and number of spermatogony, spermatocyte, spermatid and leydig cells. Conclusion: Dexamethasone causes permanent disorders in reproductive system of male rats by inhibiting mitosis activity, increasing putative gonadotropin inhibitory hormone and impairing fetal testise development.