A new study suggests you can guess the likely sex of your baby before it's even been conceived.
Myths about inducing a certain sex for your baby have persisted for decades.
Moreover, science has previously investigated these notions, like the idea that the full moon will produce a girl.
Other studies have shown that environmental factors, such as being conceived in a time of war, economic depression, or natural disasters can alter the conception ratio of boys and girls.
In these circumstances the number of boys born was higher than the number of girls.
It's a boy thing
Doctors at Mount Sinai Hospital, Toronto monitored 1,411 women, each roughly 26 weeks prior to conception.
Of those who conceived during the study, they found that blood pressure was a key indicator of the baby's eventual sex.
Building on this, they supposed the reason was higher blood pressure, brought on by the environmental factors.
In the study at Mount Sinai Hospital, 739 boys and 672 girls were born.
According to Eureaka Alert
The mean adjusted systolic blood pressure before pregnancy was found to be higher in women who subsequently had a boy than in those who delivered a girl (106.0 vs. 103.3 mm Hg).
Dr. Ravi Retnakaran who led the study explained its implications.
[This] suggests that a woman's blood pressure before pregnancy is a previously unrecognised factor that is associated with her likelihood of delivering a boy or a girl...This novel insight may hold implications for both reproductive planning and our understanding of the fundamental mechanisms underlying the sex ratio in humans.
Under pressure to have boys
The participants were drawn from 3375 recruited in Liuyang, China.
Prior to its repeal in January 2016, China's one child policy had often produced attempts to engineer a male child at the conception process, due to their preferred status in society.
The study makes no mention of the possibility of inducing the birth of a male or female baby through higher blood pressure.
The research was published in the American Journal of Hypertension.
HT IFL Science