Why do pregnant women always have their hands over their stomachs in pictures?

This is not meant to be a criticism AT ALL, I am seriously just curious what the actual reason behind it is 😂 like when the belly is bigger I understand holding it for support I guess, but like when I see women with the tiniest bump (to the point that it is barely noticeable) and in every photo they have their hand holding the baby belly, I’m just genuinely wondering why. Is it just like, excitement and showing off about being pregnant?