How does a double life arise?
Twins are mono- and dizygotic. The first as two drops of water are similar to each other and develop when dividing one egg, fertilized by the same sperm. Both fetuses are located in a common fetal bladder and have one placenta for two. Such twins are only of the same gender, and most often are boys.
Dizygotic twins, or twins, appear with the fertilization of two eggs with a pair of spermatozoa. Moreover, conception does not always occur in one day and one of the twins may be several days older than the other. Egg cells can be either from one ovary or from two. Such conception occurs extremely rarely and occurs only in 2% of cases. Pregnancy from conception and until the birth of such a pair is often fraught with many problems.
Not everyone knows, but since this type of research appeared, like ultrasound, it was possible to find out that a double pregnancy occurs much more often than the same births. That is, a woman conceives two babies, but at the initial stage of development (usually in the first trimester) one of the pair ceases to develop and only one baby is born.
This can be determined when the examination is carried out at 5-8 weeks and after some time again. The first ultrasound clearly visualizes two fetal eggs, and then one, or disappears completely, or stops in development. The development of the second child from the very conception to the birth takes place according to the scenario of single-pregnancy.
Problems of multiple pregnancies
Doubles, or dizygotic twins having different fetal blisters and placenta, do not depend on each other and do not interfere with development. But, of course, mummy, who bore double happiness, is twice as hard as when single-pregnancy. Toxicosis, swelling, overweight, kidney and liver problems overcome such a pregnant woman twice as often, and life from conception to the birth of babies is very difficult, and sometimes even with a risk to the health of the mother.
The same situation lies in wait for the mother of monozygotic twins. But here, in addition to the problem of bearing, difficulties arise with the development of one of the pairs. As a rule, the difference in weight among toddlers reaches one and a half kilograms, when the smaller child lags behind all the indicators from the older one.
This is due to the fact that the babies from one placenta feed, and the one who takes the most of the nutrients more strongly. In addition, there is a concept of so-called donation, when one of the twins begins to feed and grow at the expense of the second.