Editing Endocrine system (section)

====Male gonadal development====
For males, the [[Testicles|testes]] form at six fetal weeks and the sertoli cells begin developing by the eight week of gestation. [[SRY]], the sex-determining locus, serves to differentiate the [[Sertoli cell]]s. The Sertoli cells are the point of origin for [[anti-Müllerian hormone]]. Once synthesized, the anti-Müllerian hormone initiates the ipsilateral regression of the Müllerian tract and inhibits the development of female internal features. At 10 weeks of gestation, the Leydig cells begin to produce androgen hormones. The androgen hormone dihydrotestosterone is responsible for the development of the male external genitalia.

The testicles descend during prenatal development in a two-stage process that begins at eight weeks of gestation and continues through the middle of the third trimester. During the transabdominal stage (8 to 15 weeks of gestation), the [[Gubernaculum|gubernacular ligament]] contracts and begins to thicken. The craniosuspensory ligament begins to break down. This stage is regulated by the secretion of [[INSL3|insulin-like 3]] (INSL3), a relaxin-like factor produced by the testicles, and the INSL3 G-coupled receptor, LGR8. During the transinguinal phase (25 to 35 weeks of gestation), the testicles descend into the scrotum. This stage is regulated by androgens, the genitofemoral nerve, and calcitonin gene-related peptide. During the second and third trimester, testicular development concludes with the diminution of the fetal Leydig cells and the lengthening and coiling of the [[Seminiferous tubule|seminiferous cords]].