As soon as the pregnancy is detected, the male should be required to either consent to paying for the child or decline to pay for the child. It should also be an option that the man can decline to pay for any future children prior to the pregnancy.
That way, irresponsible women will not be able to use helpless children as financial hostages against men and society at large. You can always abort or give the child up for adoption (and if you can't because of some law or another, your highest priority should be changing that law, moving, or accept that that option has been denied to you by forces outside your control). I'm okay with the man being forced to pay for it if the child is a byproduct of his committed rape but I don't see a convicted rapist having much money for that anyway.
And I know my viewpoint angers a lot of people - especially women, but all I'm doing is holding women to as high a standard of responsibility as men. Some women like fooling around with deadbeats and as soon as the negative consequences of that show up - they immediately play the victim and demand everyone else bail them out. No....you're not a victim. You were irresponsible and the child has to pay the price for your irresponsibility.