India, July 19 -- Have you ever wondered whether having a boy or a girl is just a matter of luck? For years, most people believed that your baby's sex is purely random, a simple roll of nature's dice. But science is starting to challenge that idea.

A new study published on July 18 in the journal Science Advances suggests that your chances of having a boy or a girl aren't as random as once thought. Researchers describe the odds as more like flipping a weighted coin, unique to each family. The study found that a baby's sex may be linked to maternal age and certain genetic factors. (Also read: Your breath could reveal your identity, BMI, anxiety, depression and even sleep patterns: Study )

In theory, the odds of conceiving a boy or a girl ...