There is not enough scientific evidence to justify lowering the legal abortion limit below 24 weeks, Dawn Primarolo, the Health Minister, said today. Nothing had persuaded the Department of Health that survival rates have improved for extremely premature babies born before that time.

Pro-Life Alliance, the anti-abortion campaign group, wants the upper limit to be cut to 20 weeks. But the British Medical Association says the number of babies surviving at 24 weeks is still “extremely small”.

The Royal College of Obstetricians and Gynaecologists, and the Royal College of Nursing also maintain that the upper time limit for abortions should remain at 24 weeks.

Ms Primarolo was giving evidence this morning to the House of Commons Science and Technology Committee, which is looking at medical advances since the Abortion Act was passed in 1967 - rather than the ethical or moral issues associated with abortion time limits.

The committee also questioned Fiona Adshead, Deputy Chief Medical Officer for England.

Ms Primarolo told MPs: “The Department of Health's view and the advice to me is that - and that's why there is no proposals from the Government to amend the Act - that the Act works as intended and doesn't require further amendment at the present time.”

She said that 89 per cent of abortions were carried out before 13 weeks and 68 per cent before 10 weeks. The viability of babies born at 21 weeks was 0 per cent; at 22 weeks, 1 per cent; and 23 weeks, 11 per cent, she said.

In evidence given earlier to the Commons committee, the BMA said that, when the time limit was lowered from 28 to 24 weeks in 1990 - the last time the Abortion Act was amended - a “key argument was that this was the stage at which the foetus was considered viable”.

It added: “It needs to be acknowledged that viability is difficult to define. For example, whether it is understood to mean simply that the foetus is capable of being born alive, or at the other extreme, that it is capable of surviving through childhood with no, or minimal, disabilities.”

Ms Primarolo said today: “The medical consensus still indicates that, whilst improvements have been made in care, at the moment that concept of viability cannot constantly be pushed back.”

She also said that the capacity of a foetus to feel pain did not develop before 26 weeks, but that researchers were looking into this more closely.

According to the Department of Health, 193,000 abortions happened in England and Wales last year, of which 89 per cent were performed in the first 13 weeks of pregnancy.

The MPs' inquiry coincides with an apparent rise in the number of doctors who are conscientious objectors and will not recommend abortion on moral grounds. There is also pressure from some campaigners to relax the need for a woman to gain approval from two doctors in order to have a termination.

The BMA argues that abortion should be available to women in the first trimester on the basis of “informed consent”, and without the need for the permission of two doctors.

Evan Harris, a Liberal Democrat committee member and former hospital doctor, said that he had no problem with doctors having religious beliefs that might affect the way they wish to practice medicine: “[But]when you are in that position you have a duty to your patient not to allow those personal beliefs to influence the way you deal with them,” he told the BBC.

However, Peter Saunders, general secretary of the Christian Medical Fellowship, said thatit was not only doctors with religious beliefs who preferred not to carry out abortions. He said one in five doctors would not refer patients for the procedure.

“A woman with an unwanted pregnancy is in crisis - whether she decides to have an abortion, to keep the baby, have an adoption, whatever - that's going to affect her life forever,” he said.

Lord Steel, the architect of the 1967 Abortion Act, has said that too many abortions are now taking place and the procedure is now being used as a form of contraception. He was not persuaded that the 24-week limit should be cut, he said, but called for better sex education and a debate on sexual morality to bring the numbers down.

Roman Catholic and Church of England leaders have called for a reassessment of abortion's role in society, as the 40th anniversary of the Act is marked on Saturday.

The Archbishop of Canterbury, Rowan Williams, gave warning that abortion was regarded increasingly as normal, rather than as a procedure of last resort.

The issue of abortion will be aired again during debate on the Human Tissue and Embryos Bill next month.

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