when do boys testicles descend
As a baby boy grows inside his mother's womb, his testicles typically form inside his abdomen and move down (descend) into the scrotum shortly before birth. But in some cases, that move or descent doesn't occur, and the baby is born with a condition known as undescended testicles (or cryptorchidism). Cryptorchidism is the most common genital abnormality in boys, affecting approximately 30% of baby boys born prematurely and about 4% born at term. In about half of the babies, the undescended testicles move down or descend on their own by the sixth month of life.