Here is an interesting way to predict whether you’ll have a boy or a girl. Your blood pressure may hold the secrets to the sex of your baby. Women who have hypertension are more likely to have a boy, according to researchers from the Mount Sinai Hospital in Toronto. Recruiting 1,411 Chinese women who were planning to have a child soon, they assessed their blood pressure, cholesterol, triglycerides, and glucose levels at the start and then during their pregnancies.

What they found was that systolic blood pressure before pregnancy was higher in those women who ended up having boys. These findings were true, even after accounting for the age, education, smoking and BMI of the women.

As the study author Dr. Ravi Retnakaran explained, “In humans, the sex of the foetus is determined by the sex chromosome of the fertilising sperm.”

The study was published in the American Journal of Hypertension and the authors warned that its results are not a reason for anyone to artificially manipulate a mother’s blood pressure. The results, interestingly enough, might also explain the decrease in the number of boys who are born in countries with healthier lifestyles.