During a difficult forceps delivery, a primigravida sustains perineal trauma and subsequently reports inability to achieve orgasm and loss of sensation in the perineum. Which nerve is most likely injured?

• A Ilioinguinal nerve
• B Genitofemoral nerve
• C Pudendal nerve ✓
• D Posterior femoral cutaneous nerve

Explanation

The pudendal nerve (S2, S3, S4) is the main somatic nerve of the perineum, entering through the lesser sciatic foramen and running in Alcock's canal to supply the external anal sphincter, external urethral sphincter, skin of perineum, scrotum/labia, and clitoris/penis. Injury results in perineal sensory loss, impaired erogenous sensation, and incontinence. Pudendal nerve block at the ischial spine is used in obstetrics; injury during prolonged labor or instrumented delivery causes these symptoms.

Reference: BD Chaurasia's Human Anatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.