Sarah, what I find objectionable is that is is so completely different for the other sex.
he has no right to what goes on with the woman's body
Or to what happens to the child.
A woman can't waive her risks in the way you think a man should be able to waive his responsibilities
Not completely, no. But she can always decide on the most important thing, which is whether the baby is born or not.
Being held responsible for your own actions doesn't seem to work with some men at the moment does it, so why would they get any better with your get out of fatherhood free card?
It doesn't work with some women either, but if the whole thing were changed, and a man had actively chosen to be responsible for their child by being on the birth certificate or by not legally waiving their rights, then that could lead to men being forced to be more responsible. The law could take more power to ensure that men pay for their children, because there's a lot of men that started out wanting to play Daddy and that now haven't paid a penny for years. It could make men more accountable for their choice if they were made to make one at the start of the pregnancy, and that would work out better for all concerned.
If he doesn't want to do that, he should not leave the responsibility of contraception to everyone but himself.
I agree with this, but I think if it's going to be that way, then it has to be the same for both sexes, neither of whom have any choice over which sex they are.