FRS - Vagina

Question 1

What are the functions of the vagina?

Answer 1

1) Sexual intercourse
2) Childbirth - serves as a channel for delivery of a baby
3) Menstruation - serves as a canal for menstrual fluid and tissue to leave the body

Question 2

Anatomical postion?

Answer 2

Anterior - bladder and urethra

Posterior - rectouterine pouch, rectum and anal canal

Lateral - ureters and levator ani muscle

Question 3

Anatomical structure?

Answer 3

It is a fibromuscular structure with anterior and posterior walls - these are normally collapsed.

At the upper end, the vagina surrounds the cervix with two fornices (domes) - an anterior and posterior one.

The posterior fornix is important as it acts as a natural resevoir of semen after intravaginal ejaculation - semen liquifies eventually which can then enter the cervix canal.

Question 4

Histology of the vagina?

Answer 4

From internal to external:

1) Stratified squamous epithelium - provides protection, lubricated by cervical mucus - vagina itself doesn’t contain any mucosal glands.
2) Elastic lamina propria - dense connective tissue layer which projects papillae into the overlying epithelium. The larger veins are located here.
3) Fibromuscular layer - comprising two layers of muscles - inner circular and outer longitudinal.
4) Adventitia - a fibrous layer, providing additional support to the vagina.

Question 5

Vascular supply and lymphatics?

Answer 5

Uterine and vaginal arteries (branches of the internal iliac artery).

Venous return is by the vaginal venous plexus, which then drains into the internal iliac vein.

Lymphatic drainage -

Superior - drains into external iliac nodes

Middle - drains into internal iliac nodes

Inferior - drains into superficial inguinal nodes

Question 6

Innervation?

Answer 6

Predominantly from the autonomic nervous system.

Parasympathetic is derived the uterovaginal nerve plexus.

Inferior 1/5 of vagina receives somatic innervation by a branch of the pudendal, the deep perineal nerve.

Question 7

Clinical relevance: vaginal fistulae

Answer 7

A fistulae is an open communication between the vagina and adjacent organs.

Usually occurs as a result prolonged labour (where a caesarian section is not available. As a newborn is exerting pressure on the wall, it may cut off blood supply, resulting in necrosis.

There are three types:

1) Vesicovaginal - vagina and bladder
2) Urethrovaginal - vagina and urethra
3) Rectovaginal - vagina and rectum