This has been discussed often, but I have a spin on it that hopefully addresses the legitimate issues.

The male abortion, financial abortion, legal paternal surrender. Mostly the same thing aimed at giving a male equal opportunity to "opt-out" of a pregnancy. My own opinion on the matter is there's no reason to not extend this option to both genders, though due to facts of biology, it would have to work differently for each gender. I'll explain how I think it should work below using scenarios.

Male doesn't want child, female does: Great, but the male must declare his intentions well before the "abortion cut-off date". This gives the female enough time to change her mind if she wants, knowing that she won't have his support. The male would still bear equal financial responsibility for the pregnancy thus far, and for the abortion if the female changes her mind. The female would be required to return her intentions. If she decided on abortion after she made her reply that she wanted to keep the child, the male would not bear financial responsibility for the abortion (one should not cause financial distress by changing ones mind repeatedly). If the female decided to keep the child after the male made his intentions clear, then the male would bear equal financial responsibility for the pregnancy thus far, and that is all, he would then become nothing more than a sperm donor.

Female doesn't want child, male does: Now, nothing should take away a females right to abort. But let's say the female is willing to turn herself into just a surrogate mother, this is entirely her choice. She would be able to make her intentions known (again before the cut-off for abortion). The male could then make his reply. If he changes his mind and decides he doesn't want to raise the child alone, then the female could then re-decide on abortion, or opt for adoption (If she goes for abortion, then the situation changes to the one above, male must help pay for abortion). If she goes for adoption, the male is only responsible for the pregnancy thus far. If the male wants to keep the child, the female would only be financially responsible for the pregnancy thus far. The male would then be fully financially responsible for the pregnancy (just as a surrogate mother pays no expense).

If one parent walks away from the child, then the child suffers for it, should the parents not be forced to support the child? No. This is a decision the remaining parent must make. If they cannot afford to support the child, they should abort or adopt out. Not force the other to pay child support because they want to be a parent. Under my scenarios they must be given time to make these decisions. If they don't give each other enough time to make these decisions (I have yet to make an opinion on how much time is acceptable), then they are stuck under the current system, having to pay the other child support. Remember that some single parents are richer than some parents and their partners combined. So this decision has to be made regardless of all this.

If the father is only told of the pregnancy after the abortion cut-off date, he should not then be forced to pay child support, I would suggest he get a short time to make his decision on whether he wants to be a parent (whether the child is already born or not is irrelevant). I have yet to make an opinion on whether he should be forced to "back-pay" for the costs that the mother faced during pregnancy, but I am inclined to say no.

Reversable? What if the child wanted to know who their other parent was? It would work the same way as a kid seeking out their mothers sperm donor, or a female equivalent. What if the "no longer parent" changed their mind? Then they could make a request to have their rights and responsibilities reinstated. But this could only happen if both parents agree on it. The remaining parent could simply say "No, you had your chance".

I think I have thought of this in such a way that neither parent is stung more than the other for getting pregnant unless one chooses to keep the child. It doesn't mean the female is forced to pay for everything if the male leaves. This is a separate thing to abortion, it's equal on its own, not meant to be equal to abortion itself, as it's an option for both parents.