Women are biologically more resistant than men

I saw a video and the looked up on google and there's a bunch of scientific studies saying that when in a stressful situation such as poverty and unhealthy environments the pregnant body is more likely to produce a female. Also many mothers said that being pregnant of a boy is much harsher.

Just a thought but if you think on how many diseases are more dangerous and more likely to occur in men than women, and how the little lower demographic presence and life expectancy men have it'd come to the conclusion of men being a bit more "fragile" than women, in a sense of getting sick easier.

Also about the stressful situation thing, that would explain why rich people tend to have more sons than daughters.