How twins “turn out“?
the Birth of twins are quite unusual occurrence, twins make only 2% of newborns. When the triplets are born, it becomes known in all city as triplets are born even less often and make already 2% of the been born twins.
Polycarpous pregnancy happens different. Not all children born as a result of such pregnancy are similar at each other. There are uniovular and dvuyaytsovy twins. Dvuyaytsovy twins have such similarity among themselves as any the brother and the sister. In spite of the fact that they develop in a uterus at the same time, the time difference of their conception can make from several hours to several days. These twins develop from two impregnated ova. They can be both one, and different floor. Uniovular twins turn out at fertilization of the only ovum one spermatozoon, and as a result of division independent embryos are formed subsequently.
So far physicians cannot define the reason of such behavior of a germinal cage. Uniovular twins are similar at each other that their time own mother cannot distinguish. Such twins meet by 5 times less than dvuyaytsovy, and among them boys prevail.
the Special phenomenon - Siamese twins who have any general bodies or parts of a body. The reason of this phenomenon consists that splitting of a germ on independent forms happens later, than at origin of ordinary twins when the germ was already partly created. Siamese twins - extremely unusual occurrence. They are born once on 10 million childbirth.Germs of twins most “whimsical“
Exceptional cases of the birth of twins are partly connected by
also with the fact that not all from them get accustomed in the very first days after conception. For the woman it passes imperceptibly, and she does not even guess that she was “slightly - slightly“ is pregnant with twins. It is established that only one of 10 cases of conception comes to an end with normal pregnancy and leads to childbirth. It is impossible to plan the birth of twins. But there are quite objective reasons which increase probability of the birth of two and more kids at the same time. And it concerns only dvuyaytsovy twins because the probability of the birth of uniovular twins is always constant. It averages 3 cases on 1000 pregnancies.
Probability of conception of dvuyaytsovy twins
So, paramount value has age of the woman. The you are more senior, the more hormones develop your organism. And hormones stimulate maturing of an ovum, therefore, with growth of amount of hormones the probability of maturing of several ova ready to fertilization increases at once. Therefore for women at the age of 35 - 39 years there is a real probability of conception of dvuyaytsovy twins.
production of hormone is influenced not only by age, but also duration of light day. The best time for conception of twins - the spring when day increases and begins to warm the sun tenderly.
heredity is of Great importance. So, if in a family there are already twins, then the probability to give rise to one more couple is rather high, but it decreases with a distance in time of generation of twins.Ability to conception of twins is transferred to
only on the female line. Men can give her to the daughters, but in posterity of men of noticeable frequency of appearance of twins is not observed.
also influence of duration of a menstrual cycle on conception of twins Exists. The greatest ability to give rise to twins women whose menstrual cycle very short - 20 - 21 day, and also women with anomalies of development of a uterus, for example, in the presence of a partition in a cavity of a uterus possess or at the two-horned, as if doubled uterus., at last, twins and even triplets quite often are born
I at artificial insemination. It occurs also thanks to the hormonal preparations stimulating maturing of an ovum and an ovulation. Emergence in a family at once two or three children after many years of infertility not it an unusual occurrence.
nothing inexplicable regularity of more frequent birth of twins at various social shocks and wars Exists. Perhaps, the nature so cares for preservation of the person on the earth.