There is not enough scientific evidence to justify lowering the legal abortion limit below 24 weeks, Dawn Primarolo, the Health Minister, has said.

Appearing before the Commons Science and Technology Committee, Ms Primarolo said that nothing had persuaded the Department of Health that survival rates had improved for extremely premature babies born before that time.

The antiabortion campaign group, the ProLife Alliance, wants the upper limit cut to 20 weeks. But the British Medical Association says that the number 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 limit for abortions should remain at 24 weeks.

Ms Primarolo was giving evidence to the Select Committee, which will publish a report into the issues surrounding abortion and the medical advances since the Abortion Act was passed in 1967 – rather than the ethical or moral issues associated with time limits.

The inquiry is intended to inform a parliamentary debate expected to begin later this year over a Bill setting out changes to fertility law. MPs on both sides of the argument will use the debate as a vehicle for changes to the law by moving backbench amendments. They will also try to extend abortion law to Northern Ireland, which is exempt.

MPs expect the draft Human Tissue and Embryos Bill, one of the measures scheduled for the Queen’s Speech next month, to be introduced in the Commons before Christmas and are preparing for key debates and votes on abortion law early next year.

Evan Harris, Liberal Democrat MP for Oxford West and Abingdon and a leading pro-choice campaigner, said: “The 1967 [Abortion] Act was a humane and effective piece of legislation but would benefit from being brought up-to-date with modern clinical practice and a more respectful and modern approach to the autonomy of women, which is not dependent of getting a doctor’s permission.”

Antiabortion MPs will seek to toughen the law by lowering the upper age limit for abortions, probably triggering votes on a range of options, including 18 and 20 weeks, as well as new requirements on mandatory counselling for women seeking a termination and a “cooling-off period” for a few days. But they admit that the numbers in Parliament may be stacked against them, which is why antiabortion MPs have not initiated debates on abortion law since the upper time limit was lowered in 1990, fearing any change in the law was likely to loosen it.

Ann Widdecombe, the antiabortion Tory MP, said: “We are all geared up for the fact that there will be a very, very serious attempt to liber-alise the law. We will resist it but the parliamentary arithmetic will decide it.” By convention debates on “conscience” issues such as abortion are decided on free votes among MPs, although the Government’s position remains an important factor.

Giving evidence yesterday, Ms Primarolo said that there was no scientific evidence to support lowering the upper age limit from 24 weeks and defending the need for two doctors’ signatures to approve an abortion.

She told MPs: “The Department of Health’s view, and the advice to me, is that – and that’s why there is no proposal from the Government to amend the Act – the Act works as intended and doesn’t require further amendment at the present time.”

Antiabortion campaigners are preparing massive public campaigns to coincide with the parliamentary passage of the Human Tissue and Embryos Bill, which is set to become one of the most controversial measure of Gordon Brown’s first full session.

Some of its other measures are also likely to generate huge public and parliamentary controversy, including a move to allow gay couples jointly to seek fertility treatment. Family campaigners say that this will end the need for a father, particularly when lesbian couples undergo IVF treatment, and will mount a campaign against the change.

Another of the Bill’s provisions will extend the rules under which scientists can seek to create animal-human hybrid embryos for research purposes, which will also be controversial.

In evidence given earlier to the committee, the British Medical Association stated 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.”

According to the Department of Health, there were 193,000 abortions 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 will not recommend abortion on moral grounds. There is also pressure from some campaigners to relax the need for a woman who is seeking an abortion to gain approval from two doctors in order to have a termination.

A legal history

1861 Offences Against the Person Act makes it an offence to procure a miscarriage

1929 Infant Life Preservation Act makes it an offence intentionally to kill a child capable of being born alive, stipulated as a foetus of 28 weeks’ gestation or more

1950s Growing concern at the risk to women from backstreet abortions in postwar Britain

1967 Abortion Act, a Private Member’s Bill is piloted by the Liberal MP David Steel, making abortion legal up to 28 weeks when pregnancy is terminated by a registered medical practitioner and approved by two doctors

1970 Life, an antiabortion group commited to defending human life from conception and offering support to pregnant mothers, including with adoption, is set up

1987 An attempt by David Alton, a Liberal MP, to reduce the time limit for abortions to 18 weeks’ gestation is defeated in the House of Commons

1990 Human Fertilisation and Embryology Act reduces the upper time limit to 24 weeks, unless there is a substantial risk that the child will suffer a serious handicap or the mother risks grave physical or mental injury

1995 First Epicure study is established to determine the outcome of survival and rates of disability of extremely premature babies

2006 Second Epicure study collates data on all babies born in England at 26 weeks’ gestation or less (14 or more weeks prematurely). Data is still being analysed, but early indications suggest little improvement in survival rates to age six (between 10 and 15 per cent) of babies born before 24 weeks

Source: Times database

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