A surrogate mother established a physical and emotional bond during pregnancy that entitles her to custody of a baby that is genetically unrelated, a psychiatrist testified.

"The natural mother is the woman who gives birth to the child, and that includes whether or not the child is of her genetic origins," Dr. Michelle Harrison said Tuesday at a custody hearing over a 3-week-old boy.Harrison testified on behalf of Anna Johnson in Johnson's dispute with the baby's genetic parents, ark and Cris-pina Calvert. The Su perior Court hearing was to continue Wednesday.

The Calverts had hired Johnson to carry their baby for $10,000 and supplied the sperm and egg, but Johnson decided to back out of the deal.

The case may set precedent because the surrogate has no genetic link to the baby. The landmark Baby M case in New Jersey involved a surrogate who was also the genetic mother.

Attorneys say the California case could result in a ruling on what constitutes parenthood: the genetic link or the act of giving birth.

Johnson has said that she became attached to the baby and that the Calverts neglected her and the pregnancy. The Calverts have accused her of being motivated by money. They have custody in the meantime.

Psychologist David Chamberlain, vice president of the Prenatal and Perinatal Psychology Association of America, also testified for the surrogate. He said "nothing could be closer than a baby in utero and the birth mother." But when asked by the Calverts' attorney, Christian Van Deusen, whether the couple "have a right to their own offspring," he responded yes.

Harrison, questioned about Johnson's twice weekly visits with the baby, said Johnson believes the boy recognizes her.