This is actually pretty easy to code, it’s just a condition with various effects that happen at certain intervals. The main question is how much realism to layer in there, if we just applied expected mortality rates for pregnancy and labor with no modern medicine, there’d be a sizeable chance of death with roughly zero way to do anything about it.
Not really, an infant would need to be treated as an item for a year or so, you’d mostly carry them around, though a core feature would be feeding them frequently. I see this option as being fairly involved to add, it needs to be an active item with very complex interactions and a lot of specialized related items.
“freaky” options are definitely going to be “shot into space”. I have no interest handling rape, monster breeding, forced pregnancy, etc. in this game.