Ovulation (from lat. ovum - egg - output of a Mature, capable of fertilization of an egg from the ovarian follicle into the abdominal cavity; the stage of the menstrual cycle (ovarian cycle). Ovulation in women of childbearing age occurs periodically (every 21-35 days). The frequency of ovulation is regulated by neurohumoral mechanisms, mainly gonadotropic hormones of the anterior lobe of the pituitary gland and hormone ovarian. Ovulation contributes to the accumulation of follicular fluid and thinning of ovarian tissue located above mypetiplima pole of the follicle. Constant for every woman rhythm of ovulation is undergoing changes within 3 months after the abortion, within one year after delivery, and after 40 years, when the body is preparing for premenopausal period. Stops ovulation with the pregnancy and after the extinction of menstrual function. The appointment of ovulation is important when choosing the most effective time for fertilization, artificial insemination and in vitro fertilization.
Signs of ovulation
Subjective signs of ovulation can be transient abdominal pain. Objective signs of ovulation are increase in mucous secretions from the vagina and lower rectal (basal) temperature on the day of ovulation to increase it the next day, the increase in the concentration of progesterone in blood plasma, etc. Ovulation disorder caused by dysfunction of the hypothalamic-pituitary-ovarian system and can be caused by inflammation of the genitals, dysfunction, adrenal or thyroid gland, systemic diseases and tumors of the pituitary and hypothalamus, stressful. Anovulation in childbearing age (anovulation) is a rhythm disturbance of menstruation-type oligomenorrhea (menstruation lasting 1-2 days), amenorrhea, dysfunctional uterine bleeding. Absence of ovulation (anovulation) is always a cause of female infertility. Recovery methods of ovulation is determined by the cause of the anovulation, and require access to the gynecologist and special treatment.
Ovulation and contraception
Some women experience the peak of sexual arousal in the days of ovulation. However, the use of physiological methods of contraception against pregnancy based on sexual abstinence during ovulation, it is particularly difficult for the young couple, frequency of intercourse which reaches a fairly high level. In addition, when a strong love excitement and nervous stress can occur more ovulation (especially when episodic, irregular relations) and then for one menstrual cycle Matures not one but two eggs. Keep this in mind, choosing a particular method of contraception.
Physiology of ovulation cycle
As soon as every healthy girl aged 11-15 years begins to menstruate, which is an indicator of the readiness of the body to bear children, so there are problems associated with counting the number of days of the menstrual cycle and the legitimate question of why menstruation does not occur, or Vice versa, why not comes the long awaited pregnancy. It makes a woman all the time to think and wait to be ignorant, what is happening to her every month. And so every month for the past dozen years.
The duration of the menstrual period and cycle
Ideal menstruation lasts 3-5 days and repeated every 28 days. However, a few women, this loop takes 19 days and even less, and in others it lasts from 35 to 45 days, which is a feature of their body, and not a violation of the menstrual function. Duration of menstruation depending on the body may vary within a week. All this should not cause anxiety in women, but the delay is more than two months, called optometria or more than six months - amenorrhea, should alert a woman and make sure to find out the reason with the doctor-gynecologist.
The duration of the menstrual cycle
The menstrual cycle is a complex physiological process in women up to 45 - 55 years. It is governed by the so-called sexual centers located in the middle part of the intermediate brain - the hypothalamus. Changes in menstrual cycle, being most pronounced in the uterus and ovaries. In the ovary under the influence of hormones produced by the ovarian follicles, partly by the adrenal cortex and testes, growth and maturation of the main follicle contains the egg. The Mature follicle ruptures and the egg together with follicular fluid into the abdominal cavity, and then into the fallopian tube. The process of rupture of the follicle and release of his oral Mature (suitable for fertilization of the egg is called ovulation, which is when a 28-day cycle occurs most often between the 13th and 15th days.
Yellow body, estrogen, progesterone
On the site of a ruptured follicle is formed yellow body. These morphological changes in the ovary accompanied by secretion of sex steroid hormones - estrogen and progesterone. Estrogens are excreted ripening follicle and progesterone - yellow body.
The secretion of estrogen has two high during ovulation and during the period of maximum activity of the yellow body. For example, if the normal estrogen content is about 10 ág/l during ovulation it is about 50 µg/l, and during pregnancy, especially towards the end of it, the content of estrogen in the blood increases to 70-80 µg/l due to a sharp increase in the biosynthesis of estrogen in the placenta.
Together with progesterone estrogen promotes implantation (implementation) of a fertilized egg, keep the pregnancy and facilitate childbirth. Estrogens play an important role in the regulation of many biochemical processes involved in carbohydrate metabolism, in the distribution of lipids, stimulates the synthesis of amino acids, nucleic acids and proteins. Estrogen promotes the deposition of calcium in bone tissue, the delay selection from the body of sodium, potassium, phosphorus and water, that is, increase their concentration in blood and electrolytes (urine, saliva, nasal secretions, tears) of the body.
The secretion of estrogen is controlled by the anterior pituitary gland and its gonadotrophin hormones: follicle-stimulating (FSH) and luteinizing (LH).
Under the influence of estrogen in the first phase of the menstrual cycle, called folliculinum, in the uterus occurs regeneration, restoration and expansion of its mucous membrane - the endometrium, the growth of glands, which are long and become tortuous. The mucous membrane of the uterus thickens in 4-5 times. In the glands of the cervix increases the excretion of mucous secretions, cervical canal expands, becomes easily passable for sperm. In the mammary glands is growth of epithelium within the mammary moves.
Luteal phase
In the second phase, called lutein (from the Latin word luteus - yellow), under the influence of progesterone, the intensity of metabolic processes in the body decreases. Overgrowth of the mucous membrane of the uterus stops, it becomes friable, edematous, glands appears the secret that creates favourable conditions to attach to the mucous membrane of the fertilized oocyte and embryo development. Cancer stop mucus, cervical canal is closed. In mammary glands from overgrown epithelium end of the departments of dairy moves occur alveoli, capable of production and secretion of milk.
If pregnancy does not occur, yellow body dies, the functional layer of the endometrium sloughs, menstruation arrives. Monthly bleeding vary from three to seven days, the number of lost blood is from 40 to 150 g.
The timing of ovulation
It should be noted that different women there is a noticeable difference in the timing of ovulation. And even among the same women the exact timing varies in different months. Some women's cycles are characterized by exceptional irregularity. In other cases, the cycles can be longer or shorter than the average 14 days. In rare cases, women with very short cycle, ovulation occurs around the end of the period of menstrual bleeding, but still in most cases, ovulation will occur quite regularly.
If for one reason or another, ovulation does not occur, the layer of the endometrium in the uterus thrown out during menstruation. But if there was a fusion of egg and sperm, the egg cytoplasm begins very strongly to vibrate, as if the egg is experiencing orgasm. The penetration of sperm - final stage of maturation of the oocyte. From the sperm only its nucleus, where tightly Packed 23 chromosomes (half the number of standard cells). The nucleus of the spermatozoon is now fast approaching the egg nucleus, containing 23 chromosomes. Two cores slowly touch. Shell them dissolve and merge, which they divided into pairs to form 46 chromosomes. Of the 23 chromosomes of the sperm cell 22 is completely analogous to the chromosomes of the oocyte. They define all the physical characteristics of a person in addition to floor -. In the remaining pair from the egg is always an X chromosome and the sperm can be X or Y chromosome. Thus, if in this set is 2 XX chromosomes, born girl, if HOO, boy.
Ovulation, conception, and sex of the child
Studies conducted in the National Institute of medical problems of the environment" (North Carolina) showed that from the time of conception to the time of ovulation depends not only the conception of a child, but his floor.
The probability of conception maximum on the day of ovulation and is estimated at about 33%. High probability is also celebrated on the day before ovulation - 31%, two days before it was 27%. Five days before ovulation, the probability of conception is estimated at 10% for four days before ovulation is 14% and for three days - 16%. Six days before ovulation and the day after ovulation, the probability of conception with intercourse is very small.
When you consider that the average "lifespan" of sperm is 2-3 days (in rare cases it reaches 5-7 days), and the female egg remains viable for about 12-24 hours, the maximum duration of the "dangerous" period is 6-9 days and "dangerous" period corresponds to a phase of slow growth (6-7 days) and rapid decline (1-2 days) before and after the day of ovulation, respectively. Ovulation, as noted above, divides the menstrual cycle into two phases: the phase of maturation of the follicle, which when the average duration of the cycle is 10-16 days and luteal phase (phase yellow body), which is stable, does not depend on the duration of the menstrual cycle and is 12-16 days. Phase yellow body belongs to the period of absolute infertility, he begins 1-2 days after ovulation and ends with the beginning of a new period starts.
The pursuit of oocytes
Source:
MissFit
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