Battle of the sexes?

I've recently read an article and heard from a close friend that baby girls are easier to carry than baby boys are, and it has a lot to do with the placenta and I'm not entirely sure about this study or subject. I've heard and read that most miscarriage, still births, preterm birth etc. are more likely to happen while pregnant with a boy. Well my question to you is: Do you think it is true? And from your experience do you find this study to be true? I myself have had one miscarriage and it happened to be a boy. Opinions?