In other cases, the cycles may be longer or shorter than average – 14 days. In rare cases, is that women with very short cycle ovulation occurs around the end of the period of menstrual bleeding, but still in most cases, ovulation occurs quite regularly. If for some reason or another ovulation does not occur, the layer of the endometrium in the uterus is thrown out during menstruation. If merged with the egg and sperm, the egg cytoplasm begins to vibrate very strongly, as if ay; experiencing orgasm. Penetration of sperm – the final stage of oocyte maturation. Of sperm is just the kernel, where the tightly packed 23 chromosomes (half the usual set of cells). Sperm nucleus is now rapidly approaches the egg nucleus, which also contains 23 chromosomes. Two cores slowly touching.
Their shell is dissolved and their merger, which they divide into pairs and form the 46 chromosomes. Of the 23 sperm chromosomes 22 are completely analogous to the egg chromosomes. They determine all the physical characteristics of a person other than sex. In the remaining pair of eggs always the X chromosome, but from the sperm can be X or Y-chromosome. Thus, if this set is 2 xx chromosomes, then a girl, and if xy, then a boy.
Studies conducted in the ‘National Institute for Medical Problems of the Environment “(North Carolina) showed that from the time of conception in relation to the time of ovulation depends on not only the conception of the child, but his floor. The probability of conception is maximal on the day of ovulation and is estimated at 33%. High probability is also celebrated on the day before ovulation – 31%, two days before her – 27%. Five days before ovulation the probability of conception is estimated to be 10% in four days – 14% and in three days – 16%. Six days before ovulation and the day after her the probability of conception during sexual intercourse is very low. If we consider that the average ‘life expectancy’ sperm 2-3 days (in rare cases, it reaches 5-7 days), and the female egg cell retains viability for about 12-24 hours, the maximum duration of ‘dangerous’ period of 6-9 days and “dangerous” period corresponds to the phase of slow growth (6-7 days) and rapid decline (1-2 days) before and after the day of ovulation respectively. Ovulation, as we noted above, divides the menstrual cycle into two phases: follicular maturation, which is an average cycle duration is 10-16 days and the luteal phase (luteal phase), which is stable, not depending on the length of the menstrual cycle and is 12-16 days. Luteal phase was attributed to the period of absolute sterility, it starts 1-2 days after ovulation and ends with the onset of the new period.