labia minora

labia minora, in the female reproductive system, two thin folds of skin situated within the vulva, lying between the outer labia majora and surrounding the openings of the vagina and the urethra. The labia minora lack fatty tissue and hair, and their skin surface is rich in sebaceous and sweat glands. They vary greatly in size, shape, and color among individuals.

Anatomically, the anterior, upper folds of the labia minora wrap around the clitoris—the structure in the female genitalia corresponding to the glans penis (excluding the urethra) in the male genitalia—to form the prepuce of the clitoris (or clitoral hood). The lower portion of each fold then passes beneath the clitoris to form its frenulum, before extending in the posterior direction, edging around the vulvar vestibule. The two labia minora are joined at the back across the midline by their frenulum, which becomes stretched during childbirth.

The labia minora serve important protective and sexual functions. For example, they act as a shield for the vaginal and urethral openings, protecting them from friction, injury, and pathogens. They also contain a dense network of blood vessels and nerve endings, contributing to sexual arousal and sensation. During sexual stimulation, the labia minora can swell and change in color due to increased blood flow.