Until now, British mothers had to choose between traveling abroad to complete this surgery or waiting for their child to be born.

The 30-strong team was completed with two surgeries this summer by researchers from University College London (UCL), clinicians from UCL Hospital, UCL and Great Ormond Street Hospital (GOSH) and University Hospital Leuven in Belgium,

Treatment for spina bifida -- a problem with the development of the spinal cord leaving a gap or a split in the spine -- before birth gives babies a better chance in life than surgery after birth, according to the team, as babies born with spina bifida are often incapable of walking and may need a series of other operations later in life such as shunt placement (surgery to drain fluid from the brain).

Spina bifida can be caused by low intake of folic acid and certain medications taken by women during pregnancy, but genetics also plays a role. Six in every 10,000 UK births are affected by spina bifida.

"In spina bifida, the spinal canal does not close completely in the womb, leaving the spinal cord exposed from an early stage in pregnancy. This results in changes to the brain, as well as severe permanent damages to the nerves on the lower half of the body," said lead neurosurgeon Dr. Dominic Thompson of GOSH.

Closure of spina bifida while a baby is still in the womb "has been shown to improve short- and medium-term ourcomes," added lead fetal neurosurgeon Dr. Jan Deprest from UCLH. "While neither intervention is curative, in fetal surgery the defect is closed earlier, which prevents damage to the spinal cord in the last third of pregnancy."

This surgery involves making an incision, slightly larger than one made during a Caesarean section, opening the uterus to expose the spine and close the defect, then repairing the uterus to leave the baby inside.

Babies are then delivered by C-section after approximately 37 weeks.

The surgery has been performed more than 40 times in Belgium, where the UK team trained, with some patients being English women, since 2012. It was pioneered in the Children's Hospital of Philadelphia by Dr. N. Scott Adzick's team. The US hospital has completed over 320 such procedures since 2011.

The treatment has been offered only now for the first time in Britain largely due to the "number of procedural and ethical and training issues that have to be in place" for the fetal surgery, Thompson told CNN. The delay reflects the amount of training and infrastructure needed for the operation to take place safely, according to the surgeon.

Another factor that slowed down the introduction is the nature of this surgery, which concerns two patients, the child and the mother, and could therefore carry risks for the mother.

The UK team has been working for three years to bring the fetal surgery to Britain. Professor Anna David at UCL Hospital stated that the decision to perform the procedure in the UK was based on a large US-based trial, which showed that prenatal surgery to correct spina bifida was associated with a 50% reduction in need for surgical shunt placement in newborn babies and improvement of motor function at 30 months of age.

"The reduction in need for shunts is particularly important," said Professor Paolo De Coppi of the UCL Great Ormond Street Institute of Child Health, "as long-term follow-up of children that have undergone prenatal closure in the womb suggests that brain function, mobility and total independence were higher in non-shunted than shunted children aged 5."

Not all babies with the condition benefit from fetal repair, which doctors take into account. Thompson explained that as with all surgeries, the benefits and risks have to be considered. Some of the risks involved in this surgery are damage to the uterus or womb, premature births and infections.

"Not all [cases] are suitable, we select those where benefit is greatest and risk can be justified," he said. Cases such as mothers who carry more than one child are not suitable for the surgery; babies found to have other congenital abnormalities or additional malformations will also not be approved for the fetal surgery.

About eight babies are born with the condition every day in the United States, according to the US-based Spina Bifida Association.

"The trouble with spina bifida is that children are born with a range of disabilities," said Thompson. But, "by doing the surgery before the child is born some of the problems of spina bifida -- it appears we can reverse those."

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