The baby developed outside the womb

Reports from South Africa say Nhlahla, whose name means "luck" in Zulu, is only the fourth baby ever to survive such a pregnancy.

In all, there have only been 14 documented cases of a child developing in this way.

Nhlahla was born after specialists performed a difficult operation to deliver her on Tuesday.

The mother is at a huge risk

Professor James Walker, Ectopic Pregnancy Trust,

She had to be put on oxygen after her birth, where she weighed a healthy 2.8kg, but was breathing without aid by Thursday.

Doctors said Nhlahla and her mother Ncise Cwayita, 20 - whose first baby was born normally - were both doing well.

Liver specialist Professor Jack Krige, who helped deliver the baby, told a South African newspaper: "She is the real thing. She is truly a miracle baby."

Risks

When an egg is fertilised, it normally travels down the fallopian tube to the womb, where it implants and grows.

But sometimes, the embryo implants in the fallopian tube, a standard ectopic pregnancy.

In some cases - around one in 100,000 pregnancies - it falls out of the fallopian tube and can implant anywhere in the abdomen.

In extremely rare cases, such as this one, the embryo attaches itself to the liver, a very rich source of blood.

The baby is protected because it is within the placenta - but it does not have the usual protection of the womb - and is at more risk in the abdominal cavity.

Most babies in extrauterine (out of the uterus) pregnancies die within a few weeks.

Window

In this case, doctors only discovered the baby was growing in the liver when they performed a scan this week.

Her womb was found to be empty, even though her baby was due in a week.

Ms Cwayita was transferred to the Groote Schuur Hospital in Cape Town.

Dr Bruce Howard told the Cape Argus newspaper said: "We knew it was an extrauterine pregnancy but we didn't know it was in the liver until we started the operation on Tuesday morning."

Doctors found a small "window" where the amniotic sac connected with the outside of the liver where they were able to go in to deliver the baby.

Doctors had to leave the placenta and amniotic sac in the liver, because the mother's life would have been at risk.

It is expected they will be absorbed back into her body.

Professor James Walker, president of the British Ectopic Pregnancy Trust, told BBC News Online abdominal pregnancies could be very dangerous.

"The mother is at a huge risk. One in 200 women die before we can do anything to help them.

"The main problem for the baby is that it is not protected by the muscular wall of the womb."