The premature infants were being treated at the hospital's neonatal intensive care unit, but few additional details were available, the Philadelphia Inquirer reported.
The children were born Wednesday and the family is "local," hospital spokeswoman Linda Millevoi said.
Millevoi wouldn't name the mother; she said the hospital would release more information "in the near future and at the family's discretion."
Of the 4.2 million births in the United States in 2008, just 46 were quintuplets or larger groups of multiples, the U.S. Department of Health and Human Services said.
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