TummyMommy
A TummyMommy is a woman who carries a baby and then the baby is raised by someone else. The TummyMommy could be a birth mother or a surrogate mother.
My child's TummyMommy carried him in her tummy until he was born. Then he came home with me.

We visited my son's TummyMommy over the holiday break and saw all our extended family.