Anatomical Areas of the Vulva and Perineum
The vulva consists of the mons pubis, labia majora, labia minora, clitoris (including the clitoral hood and glans clitoris), vestibule (including the vaginal introitus, external urethral meatus/periurethra), Bartholin glands (greater vestibular glands), and Skene glands (lesser vestibular/paraurethral glands) 1, 2. The perineum is the diamond-shaped region between the symphysis pubis and coccyx, divided into the anterior urogenital triangle and posterior anal triangle, with the perineal body serving as the central fibromuscular structure 3, 4.
External Vulvar Structures
The mons pubis is the fatty tissue overlying the pubic symphysis 1, 2.
The labia majora are the outer, hair-bearing folds that extend from the mons pubis posteriorly to the perineum 1, 2, 4.
The labia minora are the inner, hairless folds located medial to the labia majora 1, 2, 4.
The clitoris includes multiple components:
- The glans clitoris (external visible portion)
- The clitoral hood (prepuce covering the glans)
- The clitoral body and crura (internal erectile tissue extending posteriorly) 1, 2
Vestibular Region
The vestibule is the area bounded by the labia minora laterally, containing several critical structures 1, 2:
- Vaginal introitus: The opening to the vagina, representing the transition between external and internal genitalia 1, 5
- External urethral meatus/periurethra: The urethral opening and surrounding tissue 1, 5
- Bartholin glands: Paired greater vestibular glands located posterolaterally at approximately 4 and 8 o'clock positions relative to the vaginal opening 1, 3
- Skene glands: Lesser vestibular or paraurethral glands located adjacent to the urethra 1
Perineal Anatomy
The perineum is divided into two triangles 3, 4:
- Anterior urogenital triangle: Contains the vulvar structures described above
- Posterior anal triangle: Contains the anus and anal canal 3
The perineal body is the central fibromuscular structure between the vaginal introitus and anus, serving as a critical attachment point for pelvic floor muscles 4, 6.
Deep Supporting Structures
The levator ani muscle with its fascia forms the pelvic floor and provides support to all pelvic organs through the perineal membrane, which connects superficial vulvar structures to deep pelvic musculature 4, 6. The endopelvic (visceral) fascia surrounds pelvic organs and connects them to pelvic walls, continuous with paraurethral and paravaginal fascia 4.
Clinical Relevance
Most vulvar cancers occur in the labia majora, though other sites include labia minora, clitoris, mons, or perineum 7. Understanding that tumors located within 2 cm of the vulvar midline require bilateral inguinofemoral lymphadenectomy, while lateral tumors >2 cm from midline may be managed with unilateral approaches 7, demonstrates why precise anatomic knowledge is essential for surgical planning.