The girls, named Abby, Brin and Laurel, were born to Hannah and Tom Hepner, of Quincy, on Nov. 22, the Sacramento Bee reported.
"Identical triplets are anywhere from one-in-a-million and one-in-a hundred million," said Dr. William M. Gilbert, medical director of Sutter Women's Services and founder of Moms of Multiples Center. "It is so rare that it is hard to calculate how frequently they occur."
"We are thinking of bottling the water in Quincy and offering it as a fertility treatment," said Tom Hepner, 33.
Doctors at the hospital said the girls will be allowed to go home after they can maintain their body temperature, eat properly, and put on some weight; at birth, Abby weighed 3 pounds, 2 ounces, Brin was 3 pounds, 11 ounces, and Laurel was 4 pounds.
"We understand that they are going to be individuals," Hannah Hepner, 29, said. "We look forward to finding out who those individuals are and helping them along the way."