Medic then decides to get himself pregnant with the seed of other species - dogs, baboons, bugs, you name it. If he can gestate those offspring just fine, surely he'd have no issue bringing a human embryo to term. Ends up developing an intense desire (and fetish) to be constantly knocked up and subsequently give birth. As for him caring for his offspring? Hell no, he has better things to do with his time - like getting pregnant again!