Vagina
Vagina: Latin = sheath;
Vagina is fibromuscular tube extending from the vulva superiorly and to the uterus posteriorly, forming female copulatory organ. Vagina is around 8cm long anterioly and 10 cm long posteriorly.
Functions
- genital canal
- excretory duct for menstrual flow
- forms part of the birth canal
Description
Vagina is situated behind the bladder and in front of the rectum. It is directed upward and backward, opening forward. Its axis forms an angle of over 90° with that of the uterus. The anterior and posterior vaginal walls are normally opposed to each other. The upper end of anterior wall pierced by the cervix
Area of vaginal lumen is divided into 4 regions or fornices:
- anterior fornix
- posterior fornix – through which rectouterine pouch can be accessed
- right lateral fornix
- left lateral fornix
The vaginal orifice is covered by a thin hymen in virgins that is perforated at the center. After childbirth, hymen consists only of tags called hymenal caruncles.
Blood Supply
Arteries
vaginal artery – from internal iliac
vaginal branch of uterine artery
Veins – form a plexus around the vagina that drains into the internal iliac v.
Lymph Drainage – external and internal iliac nodes, superficial inguinal nodes
Nerve Supply
The lower one third of the vagina is pain sensitive and supplied by pudendal nerve.
The upper two third of the vagina is pain insensitive and supplied by sympathetic (L1 & L2) and parasympathetic (S2 & S3) from the inferior hypogastric plexuses.
Clinical significance:
- Per vaginal examination: The following structures can be appreciated
Anteriorly- the urinary bladder & the pubic symphysis
Posteriorly- the rectum and the Douglas pouch.
Laterally- the ovary, the uterine tube and the lateral pelvic wall - Abnormal communication may exist between the vagina and other structures.
Namely: vesico- vaginal fistula, urethra- vaginal fistula and recto-vaginal fistula.