When mother Suzanne Libby discovered her newborn baby boy was missing from the nursery at Virginia Hospital Center in Arlington County, she frantically searched until she found the child in another room, where he had just been breastfed by the other woman, The Washington Post reported Wednesday.
A hospital aide had neglected to match the baby's ID band with the other woman's, the newspaper said.
Accurate numbers on such mix-ups are hard to come by, health experts said, since many states do not require them to be reported unless there is serious harm.
Ruth Lawrence, a breastfeeding expert at the American Academy of Pediatrics, said she hears about such incidents occasionally.
At least eight other mix-ups have occurred in recent years, she said.
Experts said the potential for harm to infants is minimal but federal authorities said the possible exposure to HIV or other infectious diseases should be treated just like an accidental exposure to other body fluids.
In the Virginia incident, hospital authorities conducted blood tests on the woman who breastfed Libby's baby that showed she did not have HIV or hepatitis, diseases that can be passed to a baby during breastfeeding.