The vagina is a potential space connecting (via the cervix) the vulva to the uterus. The vagina has extensible folded muscular walls with the rectum running behind the posterior wall and the bladder lying above the anterior wall. The cervix projects into the vault at the top of the vagina. The projection of the cervix defines the four vaginal fornices (anterior, posterior, and two lateral).
The vagina is an acid environment (due to the presence of lactobacilli) which help to discourage infection. Vaginal lactobacilli are present from puberty to the menopause.
Last reviewed 01/2018