It can be called congenital. And there is no way to correct the problem.
In the UK, fertility, child health, pregnant women and new mothers are taken very seriously. Even the royal family is involved in popularizing knowledge about postpartum depression, the benefits of breastfeeding and other important things. Under the patronage of monarchs, a lot of research is going on to reduce health problems in babies and their mothers. And at the University of Sheffield (in Britain, of course) they made another scientific discovery. Scientists have named another reason why women cannot conceive in any way. Moreover, for the same reason, girls cannot get married and remain single for the rest of their lives. And you will never believe what is the cause of these misfortunes.
It turns out that women who have a twin brother are at risk! To find out, scientists studied Finnish church records (analogs of documents that are now in the registry office. – Ed.) From 1734 to 1888. Such a period was taken to exclude the influence of external factors: modern reproductive medicine, contraception, and in general the level of women’s independence. Researchers tracked the lives of 754 women who had twins. And it turned out that girls who were born “in pairs” with boys were 25 percent less likely to give birth to children. In addition, they were 15 percent less likely to get married than their “colleagues” who were born with a sister.
Scientists suggest that testosterone is to blame. Boys need him more than girls. And they “reward” the sister with an excess dose of this hormone while still in the womb. This is reflected in the appearance of the twin girl. And, apparently, also on her further destiny. But the twin sisters were not so “malicious”.