The vaginal process (or processus vaginalis) is an embryonic developmental outpouching of the parietal peritoneum.

[2] Failure of closure of the vaginal process leads to the propensity to develop a number of abnormalities.

Peritoneal fluid can travel down a patent vaginal process leading to the formation of a hydrocele.

Accumulation of blood in a persistent processus vaginalis could result in a hematocele.

Congenital malformation of the vaginal process is also the leading cause of testicular torsion, since lack of attachment to the inner lining of the scrotum leaves the testicles free to twist.