Virilization 689628 225734132 2008-07-15T03:42:37Z Gene53945 7471764 /* Normal virilization */ In biology and medicine, '''virilization''' refers to the biological development of [[sex differences]], changes which make a [[male]] body different from a [[female]] body. Most of the changes of virilization are produced by [[androgen]]s. Virilization is most commonly used in three medical and [[biology of gender]] contexts: prenatal [[sexual differentiation]], the postnatal changes of normal male [[puberty]], and excessive androgen effects in girls or women. ==Prenatal virilization== In the prenatal period, virilization refers to closure of the [[perineum]], thinning and rugation of the [[scrotum]], growth of the [[phallus]], and closure of the [[urethral groove]] to the tip of the [[penis]]. In this context ''masculinization'' is synonymous with virilization. Prenatal virilization of genetic females and undervirilization of genetic males are common causes of [[ambiguous genitalia]] and [[intersex]] conditions. ''Undervirilization'' can occur if a genetic male cannot produce enough androgen or the body tissues cannot respond to it. Extreme undervirilization occurs when no significant androgen can be produced or the body is completely insensitive to it, and results in a female body. Partial undervirilization produces ambiguous genitalia part way between male and female. The mildest degree of undervirilization may be a slightly small penis with [[hypospadias]]. Examples of undervirilization are [[androgen insensitivity syndrome]], [[5 alpha reductase deficiency]], and some forms of [[congenital adrenal hyperplasia]]. Prenatal virilization (or masculinization) of a genetically female fetus can occur when an excessive amount of androgen is produced by the fetal [[adrenal gland]]s or is present in maternal blood. In the severest form of [[congenital adrenal hyperplasia]] complete masculinization of a genetically female fetus results in an apparently normal baby boy with no palpable [[testes]]. More often, the virilization is partial and the genitalia are ambiguous. ==Normal virilization== In common as well as medical usage, virilization often refers to the process of normal male [[puberty]], in which [[testosterone]] changes a boy's body into a man's. These effects include growth of the penis and [[testes]], accelerated growth, development of [[pubic hair]] and other androgenic hair of face, torso, and limbs, [[deepening of the voice]], increased musculature, [[thickening of the jaw]], prominence of the neck cartilage, and [[broadening of the shoulders]]. ==Abnormal childhood virilization== Virilization can occur in childhood in either boys or girls due to excessive amounts of androgens. Typical effects of virilization in children are [[pubic hair]], accelerated growth and bone maturation, increased muscle strength, [[Acne vulgaris|acne]], adult body odor, and sometimes growth of the penis. In a boy, virilization may signal [[precocious puberty]], while [[congenital adrenal hyperplasia]] and androgen producing tumors (usually) of the [[gonad]]s or adrenals are occasional causes in both sexes. ==Virilization in adolescent or adult women== Virilization in a woman can manifest as [[clitoris|clitoral]] enlargement, increased muscle strength, acne, [[hirsutism]], frontal hair thinning, deepening of the voice, and [[menstrual period|menstrual]] disruption due to [[anovulation]]. Some of the possible causes of virilization in women are: * [[Polycystic ovary syndrome]] * [[Androgen]]-producing tumors of the ** ovaries ** adrenal glands ** pituitary gland * [[Hypothyroidism]] * [[Anabolic steroid]] exposure * [[Congenital adrenal hyperplasia due to 21-hydroxylase deficiency]] (late-onset) * [[Hormone replacement therapy (female-to-male)]] == See also == *[[Sexual differentiation]] *[[Secondary sex characteristic]]s *[[Ambiguous genitalia]] *[[Androgen]] *[[Hirsutism]] {{wiktionary|virilization}} [[Category:Metabolism]] [[Category:Biology of gender]] [[Category:Physiology]] [[de:Virilisierung]] [[pl:Maskulinizacja]] [[pt:Virilização]] [[ru:Вирилизация]]