Kennedy S., McVeigh E.
The female external genitalia are described as the vulva, which is bordered by the mons veneris anteriorly and the labio-crural folds posterolaterally. The introitus tends to be open in parous women but otherwise appears closed by the apposing labia majora. The labia minora are folds of skin that fuse anteriorly to form the clitoris, which contains erectile tissue similar to the penis. The fourchette is the posterior part of the introitus, which must stretch considerably to allow the delivery of a baby. The vagina is an elastic, distensible tube, approximately 10 cm long, passing upwards and backwards from the introitus. The cervix protrudes into the vault of the vagina, dividing it into anterior, posterior and lateral fornices. Pelvic structures can be felt in the posterior and lateral fornices on bimanual examination, as the vaginal vault sits just below the pouch of Douglas (the area at the bottom of the pelvic cavity bordered by the uterus anteriorly and rectum posteriorly). The urethra and bladder neck sit above the anterior wall of the vagina; the perineal body and rectum behind the posterior wall (Fig. 76.1).