New study out on twins and sisters

Twins who share the womb with a sister may enter the world a little healthier.

A study of more than 25-hundred twin pregnancies found the risk of pre-term delivery was highest when both twins were boys and lowest when both were
girls.

The risk of other complications like low birth weight and breathing problems was also lower when at least one of the twins was a girl.

SOURCE - journal Obstetrics & Gynecology