A woman in California has stunned doctors by giving birth to octuplets - the second set of eight babies to be born in the US.

The infants - six boys and two girls - were delivered nine weeks premature by caesarean section in the space of five minutes in Bellflower, California, and stunned the medical team which was expecting only seven babies.

Weighing in at between 1lb 8oz and 3lbs 4oz each, they are said to be doing well and are in a stable condition in the neonatal intensive care unit at the Kaiser Permanente Medical Center.

But two of the babies needed some help to breath with ventilators, according to a hospital spokesman.

Hospital officials said they will be kept in incubators for at least six weeks and the mother, whose identity has not been revealed, is planning to breast feed them all.

Dr Karen Maple said: "We had an unprecedented, very exciting day in our operating room in labour and delivery, where our team of 46 physicians, nurses, respiratory therapists as well as surgical techs delivered eight babies - all live born and very vigorous. It was a truly, truly amazing delivery. The babies are currently in stable condition."

Dr Maples said she had been seeing the mother, who has not been identified, since the first trimester of her pregnancy.

And Dr Mandair Gupta, a neonatologist on the team said: "They face many obstacles due to prematurity at 30 weeks, but weight is a big consideration because the smallest baby weighs only 1lb 8oz, so that baby has a long way to go."

He added: "For the first three to seven days they are very critical, so once we are past that time we'll have a much better idea."

Nkem Chukwu gave birth to the world's first set of octuplets in Houston, Texas in 1998.

Although one baby died about a week later, the surviving children celebrated their tenth birthday last December.

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