Smegma

Smegma (Greek smēgma, "soap") is a combination of shed skin cells, skin oils, and moisture. It occurs in both male and female mammalian genitalia. In female bodies, it collects around the clitoris and in the folds of the labia minora; in males, smegma can collect under the foreskin.

The accumulation of sebum combined with dead skin cells forms smegma. Smegma clitoridis is defined as the secretion of the apocrine glands of the clitoris, in combination with desquamating epithelial cells. Glands that are located around the clitoris and the vulva majoris secrete sebum.

In males, smegma helps keep the glans moist and facilitates sexual intercourse by acting as a lubricant.

Smegma was originally thought to be produced by sebaceous glands near the frenulum called Tyson's glands; however, subsequent studies have failed to find these glands. Wright states that smegma is produced from minute microscopic protrusions of the mucosal surface of the foreskin and that living cells constantly grow towards the surface, undergo fatty degeneration, separate off, and form smegma. Parkash et al. found that smegma contains 26.6% fats and 13.3% proteins, which they judged to be consistent with necrotic epithelial debris. Newly produced smegma has a smooth, moist texture. It is thought to be rich in squalene and contain prostatic and seminal secretions, desquamated epithelial cells, and the mucin content of the urethral glands of Littré. Smegma contains Cathepsin B, lysozymes, chymotrypsin, neutrophil elastase, and cytokines, which aid the immune system.

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