Baby gorilla delivered by rare C-section at San Diego Zoo

(CNN) -- The veterinary staff at the San Diego Zoo had to perform a rare emergency C-section on one of the animals.

An 18-year-old gorilla gave birth via caesarian-section, Wednesday night.

It's a rare procedure for a gorilla.

San Diego Zoo had several outside consultants on the emergency surgery, including human neonatal specialists at UCSD Medical Center.

The baby gorilla weighed just over four-and-a-half pounds.

It had some complications, so the baby is being held in intensive care at the veterinary hospital receiving oxygen and fluids.