The Hidden Vault

What is the posterior vaginal vault?

The posterior vaginal vault (also called the posterior fornix) is a part of the upper vagina.

• The vagina surrounds the cervix, which is the lower part of the uterus.

• Where the vagina meets the cervix, it forms a ring-like space called the vaginal fornix.

• This ring is divided into four areas: anterior (front), posterior (back), and two lateral (sides).

• The posterior fornix is the deepest part of this ring, sitting just behind the cervix, closer to the rectum.

Its role during sexual intercourse:

• Depth and sensation: The posterior fornix is one of the deeper parts of the vagina, and for some people, stimulation of this area can be pleasurable, though not universally.

• Penile contact: During vaginal penetration, especially with deep thrusting or certain positions (like missionary with legs raised, doggy style, etc.), the penis can reach or press against the posterior fornix.

• Cervical contact: It’s close to the cervix, so this area can be involved in "cervical stimulation". Again, this is something that can feel good to some people and uncomfortable to others, depending on anatomy and arousal.

• Positioning for reproduction: The posterior fornix can act like a "reservoir" where semen collects after ejaculation, positioning it close to the cervix and potentially aiding in sperm transport.

Anatomical Extra Credit:

Right behind the posterior fornix is a thin membrane separating the vagina from the rectouterine pouch (also called the pouch of Douglas), which is the lowest point in the female pelvic cavity. This is sometimes accessed during certain medical procedures or when fluid accumulates due to conditions like endometriosis or infections.