Luteal phase

The luteal phase is the period of the menstrual cycle in which functional and morphological processes occur in the ovary where the follicle rupture has occurred.

Luteal phase : onset

When ovulation occurs, the granular membrane (or it is also called the wall of the graafial follicle) is broken. As a result of this rupture, the follicular fluid flows out and the egg-bearing tubercle, which contains the egg, enters the abdominal cavity. At this time, the follicle falls. When the integrity of the vascularized epithelium and the current is disturbed, the integrity of the small vessels collapses in the membrane. They are beginning to bleed to the area of the burst follicle because of a decrease in intraflexic pressure.

In this place blood coagulates, after a short time this blood clot is transformed. The remnants of the granulosa membrane (follicular epithelial cells) are combined with elements of the internal current, begin to hypertrophy and proliferate. After that, they germinate into a blood clot and a layer of epithelial large cells begins to form along the edges of the already bursted follicle. They increase in size, their bodies become more rounded and their number grows. In the cytoplasm, in the meantime, granules of the orange-yellow substance (lutein) and droplets of fat accumulate.

Depending on where the cells originated, the elements that originate from the granulosa membrane (luteal granulosa cells) and from the thea (luteinic cells) are distinguished.

Thus, a cellular unit is formed and in its central part, the remainder of the blood clot remains in the place of the bursted follicle, which has sprouted with a bundle of connective tissue. This formation was called sanguinolentum (corpus haemorrhagicum).

The substance of yellowish color - lutein - colors the formation, which already begins to increase in size, into an orange-yellow color. It was from here that the name "yellow body" or corpus luteum originated.

Along the edges, among the accumulations of yellow lutein cells, the germination of thin bundles of vessels and connective tissue begins. Because of this, a small epithelial organ is obtained, very similar in structure to the endocrine gland. The luteal phase is characterized by the fact that during its cells, which form nodules and crossbeams, fill almost the entire yellow body. So disappear all the remnants of the originally located clot cray.

Luteal phrase: ending

Over time, the yellow body grows in size. In this case, on the place of the follicle, it begins to be clearly marked out over the overall surface of the ovary. If there was no fertilization and the inoculation of the ovum, which was released even during the previous ovulation, a week later the yellow body reaches a size up to a small cherry. After this, its development is suspended and degenerative changes begin, which ends with complete regression. This body, which is formed and subjected to reverse development every 28 days, is called the "yellow body of menstruation."

The luteal phase ends in the fact that cells of this body disintegrate with time and the connective tissue is assembled in its place . After this, instead of a yellow body appears a shiny and whitish hem, which consists of a rather dense tissue. This body was called whitish or fibrous. If nevertheless there was a pregnancy, the yellow body not only remains in the ovary, it continues to increase in size and functions until the middle of pregnancy.

Due to endocrine activity, the yellow body has an overwhelming effect on other follicles. In one solo, it does not further separate the blood.

Let's sum up: the luteal phase of the menstrual cycle is the phase that comes after ovulation. In the place of the ruptured follicle appears a yellow body, When the egg is impregnated, the yellow body continues to function even half the gestation period. If the fertilization of the egg does not occur, the menstrual period begins at the appointed time.