The San Diego Zoo is home to a new baby girl gorilla, born March 12 by C-section.

The baby's mom, 18-year-old Imani, had been in labor for 12 hours, according to zoo spokeswoman Christina Simmons.

"With gorillas that's very unusual," Simmons told ABCNews.com. "Four hours is long for them."

Imani was sedated in her "bedroom" and transferred to the zoo's veterinary hospital, where the baby was delivered weighing 4.6 pounds.

"She's doing well this morning," said Simmons, adding that Imani is still resting and recovering from the surgery. "We have another gorilla spending time with her so that she has company."

The baby has yet to be named, according to Simmons.

The gestation period for gorillas is similar to that of humans - between 8.3 and 9 months, according to the zoo. But while one in three human babies is born by C-section, the procedure is extremely rare among gorillas.

"The tiny infants only weigh a few pounds at birth, and the mother is generally over 200 pounds, so the births are quick and easy," the zoo's website reads.

A baby gorilla was born by C-section at the San Diego Zoo. (Image credit: AP Photo)