Labia in the context of Urinary meatus

In mammals, the vulva (pl.: vulvas or vulvae) comprises mostly external, visible structures of the female genitalia leading into the interior of the female reproductive tract. For humans, it includes the mons pubis, labia majora, labia minora, clitoris, vestibule, urinary meatus, vaginal introitus, hymen, and openings of the vestibular glands (Bartholin's and Skene's). The folds of the outer and inner labia provide a double layer of protection for the vagina (which leads to the uterus). While the vagina is a separate part of the anatomy, colloquially the term has often been used synonymously with vulva. Pelvic floor muscles support the structures of the vulva. Other muscles of the urogenital triangle also give support.

Blood supply to the vulva comes from the three pudendal arteries. The internal pudendal veins give drainage. Afferent lymph vessels carry lymph away from the vulva to the inguinal lymph nodes. The nerves that supply the vulva are the pudendal nerve, perineal nerve, ilioinguinal nerve and their branches. Blood and nerve supply to the vulva contribute to the stages of sexual arousal that are helpful in the reproduction process.

In primates, and specifically in humans, the labia majora (sg.: labium majus), also known as the outer lips or outer labia, are two prominent longitudinal skin folds that extend downward and backward from the mons pubis to the perineum. Together with the labia minora, they form the labia of the vulva.

The labia majora are homologous to the male scrotum.

The labia minora (Latin for 'smaller lips', sg.: labium minus), also known as the inner labia, inner lips, or nymphae, are two flaps of skin that are part of the primate vulva, extending outwards from the inner vaginal and urethral openings to encompass the vestibule. At the glans clitoridis, each labium splits, above forming the clitoral hood, and below the frenulum of the clitoris. At the bottom, the labia meet at the labial commissure. The labia minora vary widely in size, color and shape from individual to individual.

The labia minora are situated between the labia majora and together form the labia. The labia minora are homologous to the penile raphe and ventral penile skin in males.