In the first scenario, a mother hopefully understands what is being expected during (and after) the pregnancy. If I could do right by words, I'd call it a biological contract. Not to say that it cannot be nulled, but the consequence will at least have emotional and physical repercussion and it would result in a loss of life. The second scenario, one might hope that the father would be a good father and do right by his child, but he is not actively, or "biologically", creating his child's condition. Passing down bunk genetics may be another topic. Still, not giving a kidney would have emotional and physical repercussion and it would result in the loss of life. Because they can have similarities in their conclusions does not mean that their conditions are ethically parallel. This first scenario, the mother engages the condition on behalf of herself and the "developing human" and, therefore, bares responsibility. In the second, the father can only respond to a dilemma which he did not engage. By proposing that these situations are comparable, you are cutting the woman's role in her pregnancy out of the picture and suggesting that pregnancy is some sort of natural abomination. (Say hi to your mom for me)
The only thing that "warrants" what a state does is your bureaucratic faux democracy (see topic). I proposed that the goal for many "pro-life" people was to see that embryos are given rights. If that were to happen, there would be a conundrum of choosing between a woman's right to an abortion and an embryo's right to gestation. It would be possible for both to occur, but it isn't practical. If it were practical, I don't think you'd resort to calling pregnancy "cancer" in effort to handwave the issue.