There is no evidence to back this up, as there has been no study published that investigates a correlation between postpartum mothers and the father's looks. So please take this with a grain of salt.

But I personally believe there may be a correlation between the father's physical attractiveness, and a mother's chance of developing postpartum depression.

I think this is what happens when women settle for a low status guy then have his kid. And they come to the realization they went through 9 months of pain, and agonizing child birth, for some loser she never genuinely loved or was attracted to. And now she's going to be stuck with his genetically inferior seed for life basically.

Whenever I hear about a postpartum mother strangling her newborn infant or drowning it in a bathtub, this is something that pops into my mind.

I also think this way, because my mother was postpartum and had to be separated from me for several weeks. This story is too personal so I won't give much details. But one of the main reasons I think my mom needed to be separated for my safety is because of my theory. My mom and dad were absolutely miserable together, and my dad to be quite frank is an ugly loser (like me) and at the time was an alcoholic/drug addict.

To be honest I have no fucking clue why they even thought having a kid would be a good idea. Maybe they thought a kid would suddenly mend thier failing marriage? Beats me. They ended up getting divorced in my teens. As soon as I turned of age my mom wanted me out and we don't contact each other much. I can't help but wonder if she'd feel the same way if she had a child with a man she loved and was attracted to?

Anyways, that's just one of my theories.