Pro-life groups are demanding answers after three appeal judges overturned a hugely controversial judgement passed down just days ago permitting doctors to terminate the baby of a woman with a learning disability.

Mrs Justice Lieven, in the Court of Protection, sided with doctors last Friday in allowing the abortion to go ahead against the wishes of the woman's mother, a Catholic, and her social worker. 

The pregnant woman, who cannot be named for legal reasons, was described as being 22 weeks pregnant and having a "moderately severe" learning disability and mood disorder.

Doctors petitioned the Court of Protection to grant the termination on the grounds that the woman would struggle to recover from the labour as well as possible separation from the baby if it were to be taken into care.

In delivering her ruling, Mrs Justice Lieven said: "I am acutely conscious of the fact that for the State to order a woman to have a termination where it appears that she doesn't want it is an immense intrusion [...] I have to operate in [her] best interests, not on society's views of termination."

However, in a surprise move on Monday, Lord Justice McCombe, Lady Justice King and Lord Justice Peter Jackson overturned the ruling in the Court of Appeal in London after the woman's mother, a former midwife, mounted a legal challenge, the Press Association reports.

They said they would give reasons for their decision at a later date.

The news has been welcomed by pro-life group, the Society for the Protection of Unborn Children. 

John Deighan, SPUC Deputy CEO, said it "beggars belief" that the abortion was granted in the first place.

"This is amazing news. The initial decision to form an abortion on a disabled woman against her will, when her mother had promised to look after the child, caused shock and outrage around the world," he said.

"A forced abortion is one of the worst things that can be done to a woman, and it is beggars belief that a judge of this land advocated this kind of cruelty and barbarity.

"We rejoice that common sense and basic decency has prevailed, and the mother and baby have escaped this appalling fate.The attention must now turn to giving this family all the support they need in an undoubtedly difficult situation.

"Serious questions must now be asked about how this decision happened, and the country will need assurances that this will never happen again."

The about-turn comes after a petition launched by another pro-life group, Right to Life, challenging the abortion was signed over 85,000 times in just over two days. 

Right to Life spokesperson Clare McCarthy said: "This is a very welcome decision that will save the life of the unborn child and the mother from a forced late-term abortion and much undue distress. However, the horrific original ruling should never have happened.

"Unfortunately, we fear that this is not a one-off case.

"We are calling on the Department of Health to urgently reveal how many women have been forced to have an abortion in the UK over the last 10 years and make it clear how they will ensure it will not happen again."