Please don't think I am putting you down (though I tend in the “Natural Law” direction.) I think the question is important and needs to be examined and discussed.
So, herewith: :-)
Consider: It is “normal,” to judge by history, for some humans to enslave others. Yet we claim there are “natural rights.” (natural <- natus <- nativity => rights that come with or pertain to birth.)
Consider: Some feminists argue that if contraception is not funded by government programs, then neither should Viagra (etc.) be so funded.
IMHO the comparison is flawed because contraception interrupts the “that for the sake of which” (or one of them) the genitals are made, while Viagra restores a function lost through some defect. It would seem to make no sense to say that contraception is the same kind of thing as setting a broken arm, yet because the arm in question is a short one, that distinction is ignored.
Again, that's not meant to be an argument. It's only a hint at another view.
I also tend to the natural law side.
However, unless natural law is based on something other than human opinion, it has no definition other than popularity.
IOW, how can one define the terms of natural law? Seems to me the term is often an attempt to avoid actually proving their argument. The natural law types jump straight to claiming whatever their position is constitutes part of natural law.
Whereas what they need to do is demonstrate why it is part of natural law.