Here is my proposition on an abortion system.

F = Female

M = Male

W = Wants Child

N = Doesn't Want Child

F:W M:W = Birth, Both Full Custody

F:N M:N = Abortion (Or adoption)

F:N M:W = Abortion (Can give birth and give custody to father with NO CHILD SUPPORT)

F:W M:N = Female custody, NO CHILD SUPPORT

This eliminates the financial ruin that is child support. If you have noticed, it does give females the ability to have an abortion if they want, giving them the upper hand, but considering pregnancy is a thing, it makes sense.