The babies are born U.S. citizens, but surrogacy agency officials say that’s not a primary motivation for the parents, who typically come from European and Latin American countries where surrogacy is illegal or socially unacceptable. The parents have exhausted other options and are willing to pay about $50,000 to $100,000 — part of which goes to the surrogate — to have biological children.

No one tracks how many of the estimated 1,400 babies via surrogacy in the U.S. each year are for international parents, but one of the larger U.S. agencies, the Center for Surrogate Parenting in Encino, Calif., estimates that about half of its 104 births in 2010 were for international parents.