FEMINIZATION

From Big Medical Encyclopedia

FEMINIZATION (Latin femina woman; a synonym feminism) — development of the somatic and mental signs inherent in a female. The term «feminization» apply to designation of dynamics of puberty (see) and somatic development in women, and also to the characteristic a wedge, the sindrokhm connected with an absolute or relative hyperestrogenemia at men or resistance of target organs To androgens (see).

T. share on physiological, or isosexual (inherent to a female body), and pathological, or heterosexual (development of female psychosomatic signs in subjects with the genetic and gonadal signs inherent to a male).

Physiological feminization begins in an early embryogenesis iod influence of the estrogen (see) emitted by ovaries of mother and a placenta. T. embryonal genitalias occurs without participation of ovarian estrogen of a fruit as during all embryogenesis ovaries do not show signs of secretory activity. Between the 10th and 12th weeks of embryonic development from myullerovy channels fallopiyeva of a pipe form (uterine tubes, T.), a uterus and an upper part of a vagina (see. Urinogenital system, ontogenesis). The outgrowth of an urogenital sine of an urinogenital bosom is gradually extended in the caudal direction, dividing an urogenital sine into an urethra and a lower part of a vagina. Later the bowl-shaped entrance of the vagina with separately located the outside opening of an urethra and an entrance to a vagina surrounded with a fold of a mucous membrane — a hymen is formed. Laying of external genitals at embryos is identical, and their sexual differentiation begins only from 3rd month of pre-natal development. In the absence of laying of gonads (see. And a pla-ziya) external genitals form on female type, irrespective of a genetic floor. Further F. external genitals and development of female secondary sexual characteristics happens under the influence of estrogen of the ovaries entering the period of the endocrine activity inherent to a reproduktivnokhm I will increase in the pubertal period. T. external genitals consists in increase in small vulvar lips, final formation of a bowl-shaped form of an entrance of the vagina and hymen. T. secondary sexual characteristics includes development of mammary glands, formation of a characteristic morfogramma of a skeleton: a wide basin with lonnsh uglokhm within 90 °, rather narrow shoulders and a thorax with an acute hmechevidny shoot, and also selective distribution of hypodermic cellulose in mammary glands, buttocks and hips, formation of pilosis on female type (the horizontal line of growth of hair on a pubis, the arc-shaped — on a forehead, three-conical — on a neck).

Occurs mental F., consisting in formation of specific female sexual behavior: shyness, a coquetry, desire to be pleasant. Women are more sensitive and emotional, than men, have richer imagination and observation, at the same time most of them show less expressed tendency to the analysis and accuracy, are less vigorous. The sexual behavior of the woman is characterized by dominance of feeling of attachment and a maternal instinct. However these lines to some extent are defined by action not only female sex hormones, but also features of education of girls.

Pathological feminization at

subjects with a genetic and gonadal male is expressed in a gynecomastia (see), and also in female lines of a constitution and distribution of hypodermic cellulose. Pathological F. it is not necessary to mix with a demaskulinization, an incomplete embryonal masculinization (see Virilescence), an eunuchoidism (see), a hypogonadism (see). Underdevelopment of a penis, hypospadias (see) and even existence of a vagina and uterus at subjects with a men's genetic and gonadal floor cannot be referred to a phenomenon pathological F. They are symptoms of an incomplete (incomplete) embryonal masculinization since the underdevelopment of generative organs and a persistention of derivative embryonal myul-lerovy channels are not connected with influence of estrogen, and are a consequence of deficit of testicular androgens in the period of a morphogenesis of external genitals (12 — the 20th week of an antenatal life) and insufficient formation of an antimyullerov of hormone (anti-myullerova a factor) embryonal male gonads. Preservation at persons with a men's genetic and gonadal floor at mature age of female type of sexual pilosis should be regarded not as manifestations F., and as a delay of sexual development on an intermediate phase of normal men's pubertal development i.e. to carry to the phenomena of a hypogonadism. Eunuchoid proportions of a skeleton cannot be also considered as manifestations of feminization since they are observed at insufficiency of gonads at both floors.

Etiology. Pathological F. develops at absolute or relative excess of estrogen, exogenous or endogenous, or at resistance of bodies - Mischa - it to androgens. Pathological F. at men can appear at a hypogonadism — anarchy (see), Klaynfelter's syndrome (see Cline-feltera a syndrome), testicular feminization (see) — and also at estrogenprodutsiruyushchy tumors of testicles (see the Small egg) or adrenal glands (see), prolaktinprodutsiruyushchy tumors of a hypophysis (see), long reception of oestrogenic drugs (e.g., at cancer or adenoma of a prostate), etc.

Pathogeny. Passing

signs F. in the form of a so-called youthful gynecomastia can be observed at healthy boys during puberty. However in such cases signs F. are usually short-term and expressed poorly. The reason of their emergence consists in functional disturbances in gipotalamo - pituitary gonadal-ache system, shift fiziol. balances between quantity of the formed androgens and estrogen, periodic rises in concentration of estrogen in blood and, as a result, in increase in intensity of synthesis of prolactin (see).

Development pathological F. at deficit of androgens it is connected with disturbance fiziol. ratios between quantity of the androgens and estrogen produced respectively by testicles and bark of adrenal glands, and the gonadotropic hormones (see) synthesized by a hypophysis.

Pathological F. at excess of estrogen it is connected first of all with direct influence of female sex hormones on target organs, and also with the androgenic insufficiency which is caused braking of secretion of gonadotropic hormones excess amount of estrogen, and lack of anti-oestrogenic influence of androgens on bodies - and target tissues.

The reason of inborn resistance of bodies - and target tissues to androgens at F. can consist in disturbance of affinity of specific receptors to male sex hormones at preservation of sensitivity to estrogen, and also in genetically caused insufficiency of enzyme a steroid - and - reductases (4,5 and - a dihydrosteroid: NADF-A4-oxidoreductases; KF

1. 3. 1. 4), testosterone catalyzing transition (see) in its more active form — dihydrotestosterone.

To l and N and h e with to and e p r about I in - l e N and I pathological F. at males depend on age, it develops in Krom. During the developing of estrogenprodutsiruyushchy tumors in the dopubertatny period observe signs of premature puberty on heterosexual type: on

a row with the advent of a gynecomastia (fig. 1) there is an acceleration of growth, skeletal maturing, pilosis on a pubis at a dopubertatny structure of male external genitals can appear.

Pathological F. a neonukholevy etiology at pubertal age develops against the background of the expressed androgenic insufficiency (absolute or relative) though the last is more often shown not by feminization, but development of eunuchoid


Fig. 1. The boy of 6 years with the pathological feminization caused by kortiko-steromy: clearly the gynecomastia and the accelerated growth are visible.

phenotypical signs. At emergence of a giperestrogeniya at reproductive age its initial the wedge, manifestation is progress ir at a yushch I a demayekuliniza a tion:

FEMINIZATION the 247th


reduction of secondary pilosis on men's type, decrease in a libido and potentiality. Against the background of a demaskulinization lines of feminization progress: hypodermic cellulose is redistributed io to female type, the gynecomastia (fig. 2) develops. The most characteristic wedge, manifestations pathological F. observe at an estrogenoterapiya.

Diagnosis. Wedge, manifestations pathological F. demand careful inspection for identification of its reason from men of any age, first of all a source of a giperestrogeniya. Inspection shall include a research of concentration of estrogen and prolactin in a blood plasma, a palpation and scanning (see) testicles, a research of adrenal glands (a X-ray contrast method, scanning, etc.), a X-ray analysis of a skull (see Kraniografiya) and, if necessary, special neurosurgical obs aestivation for an exception of a prolaktinoma (see the Syndrome giperprolaktiiyemichesky hypo -


Fig. 2. Outward of the young man of 16 years with a gi-pogsnadizm: a gynecomastia, obesity

with distribution of an underfoot fatty tissue on female type, an underdevelopment of external genitals.

gonads of a-ism). At expressed F. in the pubertal period, especially in combination with the reduced sizes of testicles, the research of a karyotype (see) is necessary for an exception of a syndrome of Klaynfelter.

L echeny at detection of tumoral process — surgical, at a hypogonadism — therapy by a chorionic gonadotrophin, androgenic drugs (taking into account a form of a hypogonadism — hypo - or hyper gonadotropic).

The forecast depends on character of the basic patol. the process which caused F. At tumors the forecast is defined by timeliness and radicalism of the carried-out treatment. At not tumoral genesis of a disease the forecast for life favorable; at the expressed gynecomastia in nek-ry cases resort to cosmetic removal of mammary glands.

P r about f and l and to t and to and development pathological F. consists in early diagnosis of the basic patol. process and its timely surgical treatment or hormonal therapy.

Bibliography: Golubeva of I. V. Germ

froditizm, M., 1980; M and l to at Piece - M. and D e N Ile-Muster A. Gynecologic endocrinology, the lane from Romanians., Bucharest, 1973; Nikolaev O. V. and E. I Cockroaches. Hormonal

active tumors of bark of an adrenal gland, M., 1963; Starkova H. T. Fundamentals of clinical andrology, M., 1973; Te

rubbed E. Hormonal disturbances at men and women, the lane with polsk., Warsaw, 1968; Labhart A. Klinik der inneren Sekretion, B. u. and., 1971; Texbook of endocrinology, ed. by R. H. Williams a. o., Philadelphia a. o., 1981.

I. V. Golubeva, T. L. Kurayev.

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