Vagina Flashcards
what is the vagina?
a distensible muscular tube
approx how long is the vagina?
9cm
where does the vagina extend?
It extends upwards and backwards from the vestibule of the external genitalia, to the cervix
biological functions of the vagina?
During sexual intercourse, the vagina receives the penis and ejaculate, assisting its transport to the uterus.
Expands to provide a channel delivery of a newborn from the uterus to the outside world
canal for menstrual fluid and tissue to leave the body
which structures are anterior to the vagina?
bladder and urethra
which structures are posterior to the vagina?
rectum and anus
which structures are lateral to the vagina?
ureter and uterine artery
what is a vaginal fistula?
result of long and traumatic childbirth where caesarian section not avaliable
‘disease of poverty’
what happens as the foetus progress down the vaginal wall in vaginal fistula?
foetus cuts off blood supply and necrosis results
when does a fistula occur?
when there is an open communication between the vagina and one of the adjacent pelvic organs
what are the 3 main types of vaginal fistulae?
vesticovaginal
urethrovaginal
rectovaginal
which organs is a vesticovaginal fistulae between?
between the vagina and bladder
consequence of vesticovaginal fistulae?
urine enters the vagina constantly
which organs is a urethrovaginal fistulae between?
vagina and urethra
consequence of urethrovaginal fistulae?
urine enters the vagina during urination
which organs is a rectovaginal fistulae between?
vagina and rectum
consequence of rectovaginal fistulae?
faecal matter can enter vagina
what is the vagina composed of? (histology)
4 layers
what are the 4 histological layers of the vagina? (internal to external)
Stratified squamous epithelium lining
Elastic lamina propria
Fibromuscular layer
Adventitia
Stratified squamous epithelium lining of the vagina? (innermost)
This layer provides protection
does the vagina contain any glands?
no
what is the vagina lubricated by?
cervical mucus
lubricates stratified squamous epithelium lining (innermost)
which pH is vagina maintained at? why?
pH of ~4.5
This prevents infection by other organisms
how does the vagina maintain its low vaginal pH of ~4.5?
Oestrogen stimulates the epithelial cells (innermost) to secrete glycogen. The glycogen is digested by Lactobacillus vaginalis inhabiting the vagina to produce lactic acid and maintain a low vaginal pH of ~4.5
what is the elastic lamina propria? (2nd innermost)
A dense connective tissue layer which projects papillae into the overlying epithelium
what is located within the elastic lamina propria?
The larger veins
what does the Fibromuscular layer (3rd innermost) comprise of?
2 layers of smooth muscle; an inner circular, and an outer longitudinal layer
adventitia of vagina?
A fibrous layer, which provides additional strength to the vagina, whilst also binding it to surrounding structures
