Clinical overview
Sagittal pelvic relationships: uterus between bladder and rectum, with the posterior fornix below the pouch of Douglas.
Surgical anatomy is the substrate every gynaecological operation, ultrasound, and clinical decision sits on. A registrar who cannot name what lies one centimetre lateral to the ureter at the level of the uterine artery, or who confuses the rectovaginal septum with the pouch of Douglas, is one slip away from injury. This chapter contrasts the normal anatomy you must know cold with the common abnormal patterns (developmental, acquired, oncological) that change the operative field — because in real practice you almost never operate on textbook anatomy.
The female genital tract develops from the paramesonephric (Müllerian) ducts. Disorders along that developmental axis (agenesis, fusion, septation) account for most congenital abnormalities and frequently coexist with renal tract anomalies. Acquired distortion — fibroids, endometriosis, adhesions from previous surgery or pelvic infection, malignancy — is the more frequent operative reality.
Core knowledge
Uterine supports and the water-under-the-bridge relationship: the uterine artery crosses the ureter near the cervix.
External genitalia (vulva). Mons pubis, labia majora (homologous to scrotum), labia minora (which split anteriorly into the prepuce and frenulum of the clitoris), clitoris (glans, body, two crura), vestibule (containing the urethral and vaginal openings, paraurethral Skene's glands, and bilateral Bartholin's glands at 4 and 8 o'clock). Innervation is mostly pudendal (S2–S4); the anterior vulva receives ilioinguinal and genitofemoral branches.
Vagina. Fibromuscular tube ~7–9 cm posterior wall, ~6–8 cm anterior, with four fornices (anterior, posterior, two lateral). The posterior fornix lies directly below the pouch of Douglas — relevant for culdocentesis and for posterior colpotomy access. Lower third drains to inguinal nodes; upper two-thirds to internal/external iliac nodes (important for Vulval carcinoma and vaginal malignancy staging).