Processus vaginalis

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

It is present from around the 12th week of gestation, and commences as a peritoneal outpouching.

Gender differences
In males, it precedes the testis in their descent down within the gubernaculum, and closes. This closure occurs at any point from a few weeks before birth, to a few weeks after birth. The remaining portion around the testes becomes the tunica vaginalis.

It does not close in females. Instead, it forms the canal of Nuck.

Clinical significance
Failure of closure of the processus vaginalis leads to the propensity to develop a number of abnormalities.

Peritoneal fluid can travel down a patent processus vaginalis leading to the formation of a hydrocele.

There is the potential for an inguinal hernia to develop, although not all people with a patent processus vaginalis will develop one. The more patent the processus vaginalis, the more likely the patient is to develope a hernia.

Persistent patent processus vaginalis more common on the right than the left.