BALTIMORE — A Nigerian woman has given birth to an unusual set of quadruplets in Baltimore.

Officials at Sinai Hospital say 40-year-old Nelly Itula delivered the babies on Friday. The quads include identical twin girls and fraternal twin boys.

The babies were delivered by Caesarian section. The girls weighed slightly more than two pounds, and the boys weighed slightly more than three pounds.

Hospital officials say Itula, a teacher, came to Owings Mills in December to visit her sister when she found out she was pregnant.

She was advised to stay in the United States because of health concerns. Her husband, Frederick Itula, arrived in Baltimore from Nigeria late Saturday. The couple has no other children, and Nelly Itula had been taking fertility drugs.

The babies are being treated at the neonatal intensive care unit at Sinai and are doing fine. The family is expected to return to Nigeria when doctors say it's safe for them to travel.