The birth of twins has been a fascinating event since ancient times, and it is revered in many cultures as an extraordinary feat. A new study which has observed twins which were male and female has concluded that during the pregnancy the female is exposed to a more substantial amount of male hormones.
The amount of male hormones is more significant than in the case of pregnancies were twin girls are born, which was already anticipated but the researchers wanted to learn if the exposure can influence the female twin negatively.
Previous studies, which were conducted on animals, suggested that females who share a litter with males are a bit different in comparison to those who are a part of an all-female offspring. The differences were deemed to be so minor that you wouldn’t be able to identify them by looking at a female with the naked eye.
Girls sharing the womb with twin brothers are affected their whole life
Scandinavian countries are known for their well-planned archives. This system has allowed lots of researchers to learn exciting information as time passed and it served as a valuable tool in the progress of this study.
The study notes that girls with a twin brother have lower academic performances as their chances to graduate from high school or university are smaller than the case of girls with twin sisters. They also tend to have a lower number of children and earn less money when they reach the age of 30 and beyond. From a statistic point of view, the numbers reach 10%, but they are notable.
The next question tackled by the study implied the causes of the phenomenon. Were the differences caused by the fact that the girls grew up in the presence of brother of the same age or are they caused by exposure to testosterone and the hypothesis of twin testosterone transfer?
The study tracked almost 14,000 people from their birth and beyond the age of thirty. The results were published in a peer-reviewed journal.