QuestionSBA
QuestionChoice
This is also a muscular tunnel-like structure which forms the lower part of the uterus, connecting it to the vagina.
10014359
b
Cervix
QuestionChoice
This is the opening between the cervix and the vagina.
10014360
c
External os
QuestionChoice
This is a fibromuscular distensible structure extending posterosuperiorly from the external vaginal orifice to the cervix.
10014358
a
Vagina
QuestionChoice
This is the opening between the cervix and the uterine cavity.
10014362
e
Internal os
QuestionChoice
This is recess behind the cervix which acts as a reservoir for semen after intravaginal ejaculation.
10014361
d
Posterior fornix
Concept
Chapter
## Summary

The vagina is an elastic, muscular tube connected to the cervix superiorly and extends to the external surface through the vulva.

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## Anatomy

The vagina lies 90 degrees to the uterus - the **angle of anteversion**. The cervix projects into the anterior wall of the vagina. 

The posterior wall of the vagina is **longer** than the anterior wall.

1/3rd of the way up the vagina, some fibres of levator ani loop behind the vagina and sit lateral to it, creating a **partial sphincter**. 

## Relations

- It is related to the **rectouterine pouch**, which is located behind the posterior fornix. 
- Below the pouch, the vagina is related to the **rectum**.
- The ureters are superolateral to the vagina.

## Blood supply

The vagina is supplied by **branches of the internal iliac artery**, specifically the **uterine and vaginal arteries**. There are additional branches from teh middle rectal and pudendal arteries. 

The veins follow a similar course and drain into the internal iliac vein.

## Lymphatic drainage

- Upper three-quarters: internal and external iliac, and sacral nodes 
- Lower quarter: superficial inguinal nodes

## Function

The vagina serves a role in sexual intercourse, childbirth and menstruation.

## Clinical points
The lymphatic drainage of the vagina is important because cancers will spread first to different nodes depending on exactly where in the vagina they are located. If they are very low they will spread to the superficial inguinal nodes while high tumours will spread to iliac nodes.
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Picture
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vagina.gif
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Vagina
Topic
237
Pelvic Anatomy
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Picture
2003
33 - Vagina.png
images/7fe3r5mn1689760704756.jpg
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Topic
237
Pelvic Anatomy
Identify the annotated structure.

[lightgallery]
a