A study analyzed decades of births and found that larger families showed a distinct tendency toward all girls or all boys, ...

A massive study of over 58,000 women shows that families may have their own subtle biological bias toward having boys or ...

We commonly think that sperm determines the sex of a child, depending on whether it carries an X or Y chromosome, but a study ...

A new study finds that the odds of having a boy or girl aren’t 50-50. Instead, birth sex is associated with maternal age, specific genes and the sexes of older siblings.

Check out these unique and cool boy-girl twin names from some of our favorite celebrities — and even the iconic Egyptian ...

A new study challenges the idea that a baby's sex is pure chance. Harvard researchers studied pregnancies among US nurses.

People start assuming gender identity as soon as a person is born. Here's why one mom is sick of other parents asking if her baby is a boy or a girl.