The testis starts to descent at four months and is located in the scrotum at six months. The weight of the testis increases about 63-fold and is more correlated to the body weight than the CVR length. The sex cords increase in diameter about twofold and show a stagnant period between the fifth and ninth months. The number of the indifferent supporting cells and goncytes increases with age; however, there is a lag in the proliferation of the indifferent supporting cells between the fifth and the ninth months. At ten months some gonocytes show degenerative changes. Pre-Leydig and young Leydig cells are found in the intertubular spaces at three months and differentiate to mature Leydig cells at four months.