Prepubertal and pubertal periods

In healthy girls puberty starts with 7 to 8 years and ends by 17-18 years [Bogdanova E. A. and others, 1980]. With 7-8 years of age, the ovaries begin to produce sex hormones - estrogen and androgens, whose number is gradually increasing. The main hormone producing part of the ovaries is the cortical layer directly below tunica. In this layer among connective tissue stroma are the ovarian follicles, mainly primordial representing the egg cell surrounded by one layer of follicular epithelium. Despite the small amount of the hormones produced by the ovaries, in this age gradually manifested their influence on the organism: the formation of the skeleton of a female type, appear lanugo of armpit and pubic AgroBalt and become painful Breasts.
The ovaries gradually increase in size, becoming an oval shape and menarche have shape and form of the ovaries Mature women.
The uterus is also increasing in amount since about 2 g of its initial mass up to 7-8 g 11-15 years old. The vaginal wall thickens, it is flexible, you receive vaginal fluid, folding walls of the vagina.
With the development of the reproductive system in girls change the appearance. To 8-10 years starts to expand the pelvis, celebrated fat female type, appear pubic hair in the armpits. Later during the following 4-5 years, i.e. up to 12 - 14 years old, formed a women's body types, developing Breasts and genitals.
The main sign of sexual maturity is the appearance of menstruation. The age of the first menstruation (menarche) - 12,7-15 years [Borisov, Yu. F., Bogdanova E. A., 1971]. Under normal sexual development rhythm of menstruation is set immediately. Often there is a 28-day menstrual cycle (normothermia), rarely - 30-32 days (potpourri) and 21-24 days (antoniuse). First menstrual cycles mainly anovulatory, and then, after 6-18 months, become ovulatory. Establishing clear rhythm of menstruation is one of the main criteria properly developed the reproductive system.
Ending sexual development by 17-18 years. By this age are fully formed female phenotype: the characteristic appearance, expressed secondary sexual characteristics, corresponding to the development of the genital organs. Later, 20-22 years, ends in skeletal ossification, which is also one of the signs of the influence of sex hormones and puberty.
The pituitary and hypothalamus. The inclusion of hypothalamic regulation mechanisms of generation of gonadotropic hormones occurs in about 7-8 years. Different mechanisms of this complex regulation begin to function in a certain sequence. The first included hypothalamic mechanisms regulating the rhythm of discharge of neurohormones. Then functionally Mature Central mechanisms, stimulating the secretion of follicle-stimulating hormone (FSH), and formed the mechanisms governing cyclic secretion of luteinizing hormone (LH), i.e. occurs relationship between the mechanisms that determine the cyclic secretion gonadotropinov. Set clearly defined functional relationship between the hypothalamus and pituitary gland, inherent in the adult human body. As the establishment of rhythm and emissions releasing hormones and gonadotropinov increases hormonal ovarian function, which provides puberty.
The pituitary gland, or cerebral appendage, is located in the Turkish saddle. To the period of sexual maturity, the weight of the pituitary gland is about 0.6, pituitary there are three share: front (adenogipofiza), intermediate and rear (neurohypophysis). The front portion produces several hormones: somatotropic (CTT), thyroid-stimulating, gonadotropic and adrenocorticotropic. Rear share of deposits two hormones: vasopressin and oxytocin that come into it from the nuclei of the hypothalamus where they are synthesized. Intermediate share as if separates the anterior and posterior pituitary. Cells intermediate lobe produce melanocytestimulating a hormone that regulates the color of the skin. There is evidence that the hormone, secretory interim shares, increases the activity of the rods and cones of the retina and adjusting his eyes to the darkness.
The posterior pituitary is in close morphological and functional relationship with the hypothalamus. It is over fiber pituitary-hypothalamic tract coming from superoptimo and paraventrikulyarnoe nuclei of the hypothalamus. In the rear and intermediate fractions of a pituitary end dofaminergicheskie nerve fibers irkutnogo nucleus of the hypothalamus. Neural link front and rear share different. Most researchers believe that nerve fibers found in the anterior pituitary, penetrate it with blood vessels and belong to the sympathetic nervous system. In addition, anterior pituitary has close vascular connection with the hypothalamus which causes their anatomical and functional relationship.
In the regulation of cell functions interim shares participate as hypothalamic releasing factors, and direct neironalny innervation.
The reproductive system is considered as a complex of self-regulating system, the main links of which are the hypothalamus, pituitary gland, ovaries and uterus. The consistency of the functions of these different anatomic, morphological, physiological properties of bodies provides the Central nervous system, mainly hypothalamic Department of the brain.
In each period of life under the influence of hormones reproductive system changes the appearance girls, girls, women. Knowing physiological features of age-related changes of the woman's body throughout life, we can detect arising deviations from the norm and to conduct adequate correction.