Testicle fetal abdomen to the inguinal ring and beyond to the inguinal canal and into the scrotum. In most cases (97% full-term, 70% preterm), both testes have descended by birth. In most other cases, only one testis fails to descend (cryptorchidism) and that will probably express itself within a year. The testes grow in response to the start of spermatogenesis. Size depends on lytic function, sperm production (amount of spermatogenesis present in testis), interstitial fluid, and Sertoli cell fluid production. After puberty, the volume of the testes can be increased by over 500% as compared to the pre-pubertal size. Testicles are
Gubernaculum Gubernaculum The paired gubernacula (from Ancient Greek κυβερνάω = pilot, steer, also called the caudal genital ligament) are embryonic structures which begin as undifferentiated mesenchyme attaching to the caudal end of the gonads (testes in males and ovaries in females). As the scrotum and labia majora form in males and females respectively, the gubernaculum aids in the descent of the gonads (both testes and ovaries). The testes descend to a greater degree than the ovaries and ultimately pass through the inguinal canal. The gubernaculum is present only during the development of the urinary and reproductive organs, being replaced by distinct