The influence of sex hormones on the body of women in different age periods

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Sex hormones are the main factors responsible for the formation of women's phenotype, support the functioning of the female organism during all life. In this regard, we consider it appropriate to summarize the basic data on their impact on sexual development somatically healthy female body.
In the period of intrauterine development ovaries do not have hormonal activity. In prepubertal period revealed a small increase production of estrogens, due to age-related restructuring of the Central structures of the brain (some units limbic structures and hypothalamus), which leads to increased gonadotropic activity of the pituitary gland.
Increased secretion of estrogen causes the restructuring of the Central mechanisms of activation of the function of the pituitary and ovarian function and gradual onset of sexual maturity. Prior to the first menstruation under the influence of the hormones oestrogen develop sexual organs and appear secondary sexual characteristics: the Breasts and sexual adult. In this period of life estrogen has a General impact on the developing female body. Under the action of estrogen formed female type of skeletal structure, is typical for women deposition of fat in the breast, buttocks, thighs.
In the pubertal period gradually established cyclic menstrual function. However, coming after menarche, menstrual - anovulatory, yellow body, as a rule, is not formed. Sexual development ends about to 16-18 years.
Thus, in the period of puberty, the predominant influence of the hormones oestrogen in the body and the sexual system in particular. The Breasts continue to evolve, sexual hair growth increases. With the growth of the follicles significantly increases the secretion of estradiol (ovaries also produce in a small amount of androgens - Androstenedione and testosterone). Secretion of estradiol reaches its maximum after 1-3 days before ovulation, which is of great value to stimulate ovulation, as enhances secretion of gonadotropin-releasing hormone from the hypothalamus and the sensitivity of the anterior pituitary to action releasing hormones. This resulted in drastic increases the excretion in the blood levels of LH and LTG. Thus, the estrogenic hormones stimulate the activity of the Central structures of the reproductive system and gonadotropic function of the pituitary gland.
Simultaneously with the increased secretion of estrogen may increase the allocation 17A-oksiprogesterona, reaching a maximum in predoperatinom period, and then decreases simultaneously with the decrease of the level of estradiol. Assume that a small increase in the level of progesterone before ovulation LH stimulates the when the effects of progesterone on sensitised estrogen hypothalamic-pituitary system. Secretion by the ovaries of testosterone and Androstenedione increasing somewhat in the late follikulina phase. Dynamic changes in the secretion of androgens during the cycle is insignificant.
After predovlatorna increase the content of all ovarian hormones reduced their level in the blood. However, as the development of the yellow body there is a new increased secretion and increased secretion of sexual hormones, but in different proportions than in follikulina phase.
There is a phase of prosperity hormonal activity of the yellow body. Abruptly, 10-20 times, increase the production of progesterone and highlight it in the blood. Yellow body also produces estrogen, but in smaller amounts than in follikulina phase.