I cant find anywhere thats says if one of them was a donor ie sperm or egg. It may be that just one of them now is infertile and the other isnt and so they want a child thats a part of *them*……. its a decision either way and one that im sure wouldnt have been made lightly.
Adoption is definately another option but if the opportunity was there for a child that was at least half *theirs* im sure most couples would take that route if they could afford it
I do however agree with the idea that somewhere in the future it may well be the case that *busy celebrities* will indeed be too posh to carry their own children.