Anatomy of the female perineum and perineal pouches

Collectively called the Vulva which includes: • Mons Pubis • Labia Majora and Minora • Clitoris • Urethra • Vaginal Orifice • Vestibular Glands Mons Pubis fatty, rounded area over the pubic symphysis Labia Majora 2 fatty skin folds that are homologous with the male scrotum Labia Minora smaller folds covered with mucosa and richly supplied with sebaceous glands enclose the region called the vestibule, which contains the clitoris, urethra and vaginal orifices

Greater Vestibular Glands (Batholin's Glands) • equivalent to bulbourethral glands in males • secrete mucus containing liquid for lubrication • during sexual intercourse Lesser Vestibular Glands • also secrete mucus for lubrication Clitoris erectile tissue equivalent to glans penis housed in a hood of tissue (prepuce) formed by the junction of labia minora richly supplied by nerves and engorges with blood upon sexual arousal

Part of the adult female external genitalia Mons pubis clitoris Urethral orifice Labia majora Labia minora introitus anus

The perineum Overlies the inferior pelvic aperture The urogenital triangle s anterior to a line in front of the ischial tuberosities The muscles are grouped as Superficial –bulbospogiosus,ischiocarvenosus and superficial transverse perinei occupying the superficial perineal pouch

Superficial perineal pouch Boundaries Below-membranous layer of superficial fascia (Colle’s fascia) Above-urogenital diaphragm Laterally attached to margins of pubic arch Anteriorly communicates with space btw sup. Fascia of ant abd. Wall & its muscles

The superficial perineal pouch Contains structures forming the root of clitoris Bulbospongiosus- sorrounds orifice of vagina & covers vestibular bulbs Ischiocarvenosus-covers the crus of clitoris Superficial transverse perinei

Perineal body-wedge shaped mass of ffibrous tissue situated btw lower end of vagina & anal canal Giives attachment to perinei muscles, levatores ani & support posterior wall of vagina Perineal branch of pudendal nerve supplies skin & muscles

Deep perineal pouch Lies between the superior & inferior (perineal membrane) fascia of the urogenital diaphragm

Contents of the dep perineal pouch Deep perinei muscles-deep transverse pernei Part of the urethra Part of the vagina The sphincter urethrae (pierced by urethra and vagina) Internal pudendal vessels & their branches Dorsal nerves of clitoris

Female urethra 4cm long Opens into vestibule 2.5cm below clitoris

Episiotomy At childbirth the introitus may be enlarged by making an incision in the perineum Starts at the fourchette and extends mediolateraaly to the right side for 3cm. Structures encountered in an episiotomy include- skin, vaginal epithelium, subcutaneous fat, perineal body and superficial transverse perineal muscle

Episiotomy and perineal nerve block