The formation of oocytes in the female
The male and female participate in the production of the offspring, where the male introduces its gametes called semen, which meet during the process of sexual intercourse with the female stored in the egg called the egg, to succeed a sperm to penetrate, unite together two components of fertilized egg, A new individual with genetic traits is formed from both sides.
The formation of oocytes that represent the female begins from the first embryonic stages, and many equal divisions are divided into ovarian cells that are contained inside the vesicles that remain in the ovaries and are subjected to a process of incomplete and incomplete division, which extends for years until puberty begins. The effect of female hormones begins on the vesicles, The condition of the secondary ovarian cell by completing the stages of the equitable division if it is fertilized by a spermatozoa, to become a fertile mature egg, which later develops into a fetus.
Ovulation stage in women
Ovulation is defined as the release of a mature egg from its ovary into the fallopian tube, and the ovulation phase is developed from the menstrual cycles of the female, which include two cycles: the ovary cycle and the uterine cycle. The ovaries cycle consists of three stages called the stages of the ovary, beginning with the vesicle stage, then ovulation, then the yellow body. The cycle of the uterus also has three stages, which involves cleaning the uterus or preparing it for the fetus in case fertilization of the egg occurs at the top of the egg channel. , Development of endometrial growth, and development of secretion.
Menstruation cycle
The cycle of menstruation or menstruation is defined as the normal set of natural changes occurring in the reproductive system every month since the female reaches the uterus and the ovary to prepare it for fertilization of the eggs, and then to receive the fetus when fertilization occurs or to remove the fertilized eggs in case of absence. The female stores hundreds of thousands of eggs In their ovaries since their intermediate embryonic stages, while the production of these eggs depends on their attainment. The actual function of this monthly activity known as menstruation or menstrual cycle is to make the pregnancy possible by maturing one egg every month and to facilitate its access to the egg channel; To fertilize sperm if any.
The cycle of menstruation begins between the tenth and the 14th year of the girl. The beginning of the girl’s arrival and her biological readiness to carry a fetus in her womb. The menstrual cycle includes two cycles: the ovary and the uterus.
Ovarian cycle
The cycle of the ovary in which three phases mean the maturity of the egg and its secretion, and each phase includes several changes, as follows:
- Follicular Phase: It is the first phase of the menstrual cycle, and includes hormonal control that changes important to maturation of one egg from one of the ovaries, while the other ovary in a period of rest and rest. The changes in this phase begin with the secretion of the pituitary gland called the follicle stimulating hormone (FSH), which matures one vesicle per month. The mature follicle secrete an estrogen hormone to increase the thickness of the lining of the uterus and its vascular permeability.
- Ovulation Phase: Increased estrogen secretion from the mature follicle, which is relatively accumulating in the blood, reduces the levels of FSH by inhibiting its secretion from the pituitary gland. This is necessary to prevent the maturation of other vesicles. This is explained by limiting the ovaries to the secretion of only one egg per cycle , And on the other hand begins the secretion of the hormone activator of the yellow body, which completes the maturity of the vesicle Grave, and the occurrence of ovulation, while the optimal period of this phase is between the twelfth and sixteenth days of the menstrual cycle, while ovulation occurs in girls with the role (Luteum). The ovulation process is accompanied by an extra activity of the pituitary gland in the secretion of follicle stimulating hormone (FSH), the hormone activating the yellow body (Luteal hormone) and its shortening LH), which in turn accelerates the maturation of the egg.
- Luteal Phase: The yellow body produces progesterone and a small amount of estrogen. These hormones inhibit the production of the activated hormone of the follicle, and the activating hormone of the yellow body, so it does not produce a new vesicle as long as the yellow body is active and the uterine progesterone is present to receive fertilized egg and embryo incubation, Endometrium, caused by the secretion of glycogen and fat; to provide the appropriate environment for the development of the fetus in the case of fertilization of the egg, and the occurrence of pregnancy.
Cycle of the uterus
The cycle of the uterus includes three stages that are intended to prepare the fetus in the event of pregnancy. The stages are as follows:
- Menstrual Flow Phase: The decay of the yellow body leads to a decrease in the level of progesterone in the blood in the absence of pregnancy, which leads to a decrease in the amount of blood received to the lining of the uterus, die cells lining epithelium, and then expand blood vessels, and increases blood pumping to the uterus, With varying amounts of blood, this blood represents the menstrual phase which lasts from three days to five, after which the other ovary begins to prepare a new mature egg.
- Proliferative Phase Development: This phase involves increasing the thickness of the lining of the uterus by the effect of estrogen, which is produced by the mature graft vesicle.
- Secretory Phase: Progesterone, which is produced by the yellow body, stimulates the secretion of mucous substances from the lining of the uterus to maintain its lining in preparation for the fertilization of the fertilized egg in case of pregnancy.