When the yellow body appears
author: doctor Cazonova O.I.
The yellow body is a temporary gland of internal secretion, which produces the hormone progesterone and estrogens (estroliol and androgens), is formed and functions in the body of a woman in the second phase of the menstrual cycle after ovulation. Ovary, pituitary gland, growth factors and the immune system of women play an important role in the process of its formation and reverse development. In its composition, the yellow body has lutein, which determines the characteristic yellow color of the formation.
The main function of the yellow body is the synthesis of progesterone, which is necessary to protect and prolong the future pregnancy, reducing the contractile activity of the muscular fibers of the walls of the uterus.
The formation of the yellow body occurs in the secretory phase of menstruation for the twelfth to the sixteenth day of the cycle after the rupture of the main follicle and the release of the egg. How long does the phase of the yellow body last ? Read the link. It is at the site of the rupture that the yellow body of menstruation is formed. If fertilization does not occur, subsequent menstruation and rejection of the embryo prepared for implantation of the enlarged layer of the endometrium occurs, and the yellow body loses its functions and gradually regresses.
The process of formation and functioning of the yellow body has certain stages of development: proliferation, angiogenesis (vascularization), flowering and reverse development.
The first stage (proliferation) begins immediately after the release of the egg cell, the cells of the burst follicle actively divide and multiply, forming a temporary formation of yellow color - corpus luteum (yellow body of menstruation).
The stage of vascularization (angiogenesis) is characterized by the germination of blood vessels into epithelial cells, which actively divide and grow. For intensive progesterone production, a good blood supply is necessary, therefore it is believed that the yellow body has the most active blood flow in the body.
The third stage (the heyday of the yellow body) is characterized by the onset of hormonal activity of the yellow body. It begins with the production of progesterone and lasts from ten to twelve days (if pregnancy has not occurred) or until the formation of the placenta (if fertilization has occurred). The yellow body increases in size, reaching almost two centimeters, turning into a temporary gland producing hormones. This process is controlled by the luteinizing hormone of the pituitary (LH).
The stage of reverse development or regression of the yellow body ends with menstruation. At this stage, in connection with the lack of fertilization, stimulation of progesterone secretion stops, the amount of luteinizing hormone decreases dramatically, the yellow body stops secreting progesterone, and the uterine wall begins to contract, resulting in menstrual bleeding. In the cells of the yellow body, dystrophic changes begin, and a hyaline formation in the form of a rumen - a whitish body is formed.
With successful fertilization, the embryo enters the uterine cavity and is implanted into the endometrial layer of its wall, and its membranes begin to produce - the chorionic gonadotropin, which further stimulates the yellow body and the secretion of progesterone. Under his influence, the yellow body of menstruation actively grows and transforms into the yellow body of pregnancy, which functions in the body of a pregnant woman until the moment of placenta formation. The formed placenta develops its own progesterone, which, until the end of pregnancy, ensures the functioning of the fetoplacental system, and the yellow body of pregnancy begins the process of reverse development.
author: doctor Kuznetsov MA
The yellow body can appear either in the left or in the right ovary and not necessarily during pregnancy. This education appears in the second phase of the menstrual cycle and exerts its influence depending on the situation.
If the pregnancy has not occurred, then this Graafovy vesicle undergoes involution - it turns into a connective tissue scar. This action comes after two weeks of his active work on the preparation of the endometrium of the uterus - the mucosa for attachment and nutrition of the embryo.
author: doctor Filonenko AI
The yellow body is formed in the ovary instead of the follicle that has completed ovulation. It temporarily produces sex hormones - progesterone and estrogen. Progesterone is needed to maintain pregnancy, especially at the beginning, when the placenta itself can not yet produce the required amount of this hormone. Therefore, up to 12 weeks, this work is performed by a yellow body. On ultrasound it looks like a non-uniform rounded yellow formation of soft consistency, however, the hormonal functioning of this organ can be diagnosed only in the laboratory. For this, certain tests must be submitted.
author: doctor Kuznetsov MA
Errors in the second phase of the menstrual cycle of the luteal phase are associated with a deficiency of the yellow body or in general its absence. The lack of a yellow body in turn provokes a deficiency of progesterone - the most important component of the hormonal system during pregnancy.
author: doctor Krivega M.S.
Each woman has two ovaries, in which a few thousand (about 300 thousand) ovules are in the inactive state still in the pre-natal period. Since the age of 13, when the first menstruation begins, one or two (which happens less often) eggs mature. A mature egg leaves a small cavity, the follicle where it ripens and enters the uterine cavity in search of a sperm (which, by the way, should not be reached by one, but in several thousands accompanied by fertilization). This process of egg release is called ovulation. Every month, only one ovary is working on the maturation of the egg, but there are menstrual cycles, when ovulation does not occur at all.