Every time some group wants a new "right" enforced by coercion, they start mangling the constitution by distorting the meanings of words found therein, depending on whether reinforce or weaken their argument. Right-to-lifers tend to incorporate the Declaration into the Constitution with legal standing, followed by arguments that life begins at the moment of conception. Pro-abortionists argue that the Declaration is a "statement", since at the time of it's writing, there was no federal government and the Continental Congress had no power to make law, yet many invoke the Declaration as anti-death penalty activists.
I say the terms of surrogacy are the same as a business contract, should be clearly spelled out in advance to both the surrogate and the predecessors, i.E., the biological parents, which may be different dependent upon who the sperm and egg donors are. If both parties have had competent legal representation of their own choice prior to any contractual agreement, then the terms of the contract should be followed. In other words, it shouldn't matter who the egg, sperm or carrier was, the terms of the written contract should apply.