27 Female Perineum and External Genitalia
Female Perineum:
The external genitalia in the female anatomy are collectively known as the vulva and they make up the external structures of the female reproductive system.
The perineum runs from the coccyx in the back to the pubic symphysis in the front. It is diamond-shaped and thus can be divided into two triangular parts. The base of the triangle runs between the ischial tuberosities which is basically a line drawn half-way between the vaginal opening and the anus.
These two triangles can be described below:
- Urogenital triangle: the anterior portion containing the labia minora and labia majora, the opening of the vagina (the introitus), the urethral opening (the meatus) and the clitoris.
- Anal triangle: the posterior portion containing the anus and its surrounding muscles for defecation.
The diagram below represents the two triangles as described above:
Figure 68 Inferior view of the urogenital triangle(blue) and anal triangle(orange)
External Genitalia:
The female external genitalia are collectively known as the vulva which is comprised of several structural components:
Table 30 Female external genitalia
Structure | Description |
Labia majora | Two large folds of longitudinal skin and adipose which extend to the perineum. They serve as a window-like shutter, acting as an entrance to the more delicate structures of the vulva |
Labia minora | Two smaller folds of smooth tissue lying medial to the labia majora, which enclose the vestibule – the interior part of the vulva which contains the openings of the urethra and vagina. The labia minora has a higher density of vasculature and nerve endings than the labia majora to aid in sexual arousal. The labia minora also enclose the clitoris at its most superior portion |
Clitoris | A small, cylindrical structure located on the top of the vulva where the labia minora converge. Embryonically, the glans of the penis is homologous to the clitoris |
Vaginal orifice | The opening to the vagina |
External urethral orifice | The opening through which urine is eliminated from the body |
Figure 69 Anterior view of female external genitalia
Check out this meme about the perineum!
Hint: This meme is referencing the function of the perineum! It plays a crucial role in supporting the pelvic floor and controlling the passage of bodily functions. It also contributes to sexual function and provides structural support for the pelvic organs.