Happier populations are more likely to have baby boys than baby girls, a study says.
During periods of national euphoria such as a major sports tournament, people tend to have more sex, and on average more boys are born as a result, research following the 2010 Fifa World Cup in South Africa has found.
The study from the University of the Witwatersrand was recently published in the journal Early Human Development, and found that “hosting a major world sporting event appears to significantly influence” the gender ratio of births in a country.
This is because in humans, in the absence of significant stress, the sex ratio at birth appears to favour males, rather than females.
In short, the more elated and less stressed you are during the conception of a child, the more likely you are to have a boy.
The study concluded:
The FIFA 2010 World Cup created more optimal (less stressful) conditions for the South African population. Possible mechanisms, all operating at population level, for the observed increase in the sex ratio at birth in South Africa include more frequent sexual intercourse, unimpaired sperm quality and decreased male fetal loss.
The bump in baby boys was shown to correspond to about 1,088 extra male births than predicted for February and March of 2011 - nine months after the World Cup...
...and this moment for South African football:
We'll find out by the summer of 2016 whether the same thing happens for the English after October's Rugby World Cup.
HT: Mail & Guardian