Well, perhaps science can give a solution: Scientists created offspring for two male mice. But, I'm sure even the most diligent witchcraft of the ancients could do that and even more.
The question is not about if it can be done scientifically. If it can be done, so what? What is the big deal? It is good to have the knowledge. But the question is why do it.
An illegitimate child is still an illegitimate child, no matter how one would want to justify it.
A human being is still a human being.
The two statements can work hand in hand. One condemns the parents, the other values the child.
Perhaps it is not all condemnation. A handicapped child can come from the corrupted cursed genome of human parents; But whatever defects on a scientifically manipulated child is the responsibility of more human wrong doings. Signing any contract alone is no way to justify the refusal of such responsibility on either side (doctors or patients).