Ovulation - a process that is part of the menstrual cycle, during which the follicle ruptures, releasing the egg, which is moving on the fallopian tubes into the uterus, and there awaits fertilization.
In animals ovulation occurs differently. For example, ovulation in female camels induce pheromones
Pheromones - the road to the heart of a loved one is through the nose
male camels. In caravans with no males, females there are no heat.
In cats ovulation begins after mating. In chickens, it happens almost every day. But here we are concerned with ovulation in women.
Ovulation occurs on the fourteenth day of the menstrual cycle
The days of the menstrual cycle: Four phases
(the basis of a mean cycle length of 28 days). However, normal ovulation considered starting between the eighth and twentieth day of the menstrual cycle, as some women have a very short cycle, in others - a very long-lasting. Identify the beginning of ovulation by their appearance in most cases impossible.
Before ovulation, the follicle goes through a series of transformations necessary to ensure that the egg was subsequently able to survive. Then, an opening is formed in the follicle, through which the oocyte leaves the follicle. It enters the uterus and, if fertilization occurs, embedded in its wall, and if not, is destroyed within 24 hours.
On protyazhenib process that takes about 375 days, or 13 menstrual cycles, ovarian develops a large group of immature primordial follicles, each of which will gradually become preovulatory follicles. The preovulatory follicle contains not fully mature egg and its surrounding fluid.
Under pozdeystviem luteinizing hormone (LH), the theca cells of preovulatory follicle begin to produce androstenedione, which is converted to estradiol, a type of estrogen
Estrogen - the key to bone health
. Elevated levels of estrogen stimulates the production of hypothalamic gonadotropin-releasing hormone (GnRH), which signals the hypothalamus to release follicle stimulating hormone (FSH). Increasing concentration in the blood LH and FSH marks the beginning piriovulyatornoy phase, during which the oocyte maturation.
LH commands to the development of proteolytic enzymes that begin to destroy the follicle tissue, forming a hole through which the egg falls into the peritoneal cavity, and further - to the fimbriae (cilia) of the fallopian tubes. These fimbriae help the egg to move through fallopian tubes.
By the time the egg is passed first meiotic phase, during which formed two cells - a large secondary oocyte which comprises the entire cytoplasmic material and a small polar body inactive. Then comes the second phase of meiosis, but it stops at metaphase and so continues until fertilization. If it does not, metaphase does not continue, and the egg is destroyed in a day. Internal uterine mucosa by this time reached their maximum size, as well as cancer of the endometrium.
The life cycle of follicle is completed. Without egg it shrinks, becoming the corpus luteum, the accumulation of cells that produce estrogen and progesterone
Progesterone - norm and pathology
. These hormones cause endometrial glands begin generating proliferative endometrium place where embryos begin to rise if conception occurs. The corpus luteum continues to hormones before menstruation, after which it is gradually replaced by scar tissue.