Image caption Doctors say that the six babies - who have not been named yet - are well but under-weight

An Afghan mother has given birth to six children at a hospital in the northern city of Mazar-e-Sharif.

The woman was apparently unaware she was carrying more than one child and had not received fertility treatment.

Doctors say the mother arrived in hospital on Monday and gave birth on the same day to three boys and three girls. It was her first pregnancy.

Doctors say that having six children without fertility treatment is extremely rare.

Afghanistan has one of the highest maternal and infant mortality rates in the world.

'Brave'

The mother, named as Sharah, 24, arrived in Mazar-e-Sharif hospital from a remote village in Balkh province.

Image caption Sharah is exhausted after the unexpected birth of her six children

Provincial Health Director Mirwais Rabi told the BBC that all six babies are well but under-weight, with one only weighing about 700g (25oz).

Mr Rabi said the sextuplets were being kept inside incubators and a special team of nurses and doctors are looking after them.

The mother is said to be in good health but exhausted.

Doctors say that had they been aware that she was carrying six children, she would have been in hospital at least several days in advance.

Sharah's story has made headlines on Afghan television and radio stations.

"She is brave, she is amazing," one resident said, "I don't know how she carried six children. The government should help her now."

A 2010 survey revealed that infant and under-fives mortality rates appeared to be decreasing.

Experts say that despite recent improvements, Afghanistan remains one of the most dangerous places in the world to be a pregnant woman or a young child.

One in 10 children in Afghanistan still dies before they are five years old, the survey said.