Two of the babies were still receiving supplemental oxygen but were inhaling and exhaling on their own.
The mother, whose identity remains a secret, had not yet been able to hold any of the delicate babies - six boys and two girls - who were born weighing between 1 pound, 8 ounces and 3 pounds, 4 ounces. However, she was able to see them in their incubators Tuesday night.
In lieu of names, the babies have been assigned letters A through H, in the order of their birth Monday morning. The babies' incubators were being kept near one another in the same room for bonding, said Miriam Khoury, clinical director of inpatient obstetrical nursing at the hospital.
Four of the babies were receiving tube-feedings of donated breast milk, said Khoury.
The stomach of a fifth baby didn't absorb the milk he was given Wednesday and now was being fed intravenously, said Khoury. Two of the babies that were receiving milk also were being fed through a vein.
The mother has begun pumping breast milk in anticipation of eight hungry babies, said Serrano.
Doctors were surprised by the birth of the eighth baby, because they were only anticipating seven, said Dr. Harold Henry, one of 46 staff members who delivered the babies by cesarean section.
Khoury said the addition of eight babies to the neonatal unit had not stressed the hospital.
"This is history for us, so of course we're happy," said Khoury, who helped coordinate the materials needed for the labor.
Details about how the octuplets were conceived have not been released, but doctors not involved in the delivery believe the mother was likely on fertility treatment.
Dr. Daniel Mishell, professor of obstetrics and gynecology at the University of Southern California's Keck School of Medicine, recommends carefully monitoring pregnancies involving fertility drugs by ultrasound.
Multiple births can be dangerous for babies and their mother, and in some cases, may result in lasting health problems. However, in cases where a woman insists on having multiple births, there's a limit to a doctor's role.
"You can't mandate a reduction of pregnancies," Mishell said. "You can advise them, but you can't mandate them."
The babies were expected to remain hospitalized for several weeks and could face serious developmental delays because of their small size.
The nation's first live-birth octuplets were born three months premature in Houston in 1998. The tiniest baby, who was born at 10.3 ounces, died of heart and lung failure a week after being born. The others survived.
Mother Nkem Chukwu and father Iyke Louis Udobi had used fertility drugs in the pregnancy.
AP Science Writer Alicia Chang contributed to this report.