Dawn Primarolo told MPs that despite scientific advances, a foetus's chances of survival had not improved and the upper limit of 24 weeks should not be reduced.
However, her comments came as it emerged a British baby had been born at 23 weeks and five days and was battling to stay alive in a neo-natal unit.
Pro-life campaigners said the case should force MPs to look again at the upper limit, with a spokeswoman for the ProLife Alliance calling it "living evidence of the unborn child's strength and resilience".
With just days to go before the 40th anniversary of the Abortion Act, debate on the issue is hitting new levels of intensity, with campaigners on both sides calling for changes.
Lord Steel, the architect of the act, yesterday said too many abortions were taking place. He effectively accused some "irresponsible" women of using the procedure as a last-ditch contraceptive. He said: "I would like to see more research as to why women present for abortion.
"I suspect that a fair percentage would be found to have used failed contraceptive measures or none at all.
"Abortion should not be regarded as long-stop contraception, and as a society we need to address these issues, as well as the questions of sexual ethics and sex education."
He said he had consistently argued that if abortion was "sadly necessary" it was "desirable that it should be carried out as early as possible".
He said parliament had "always protected the viable foetus from infanticide" and said there needed to be "convincing evidence" of viability before 24 weeks to justify reducing the limit.
"As it is, very few are carried out after 22 weeks, since all are agreed that is undesirable," he added.
He called on the Commons science and technology committee, which Ms Primarolo was addressing, to look to Europe, where one doctor could approve an abortion up to the 12th or 13th week of pregnancy. UK law requires the consent of two.
The health minister told the committee that at 21 weeks gestation, the chance of survival to discharge from hospital was 0 per cent. At 22 weeks it was 1 per cent and at 23 weeks it was 11 per cent.
She said: "In this very complex area of viability we are following the medical consensus and that medical consensus still indicates that, while improvements have been made in care, at the moment that concept of viability cannot be pushed back in weeks. It's a matter of viability and survival rates and that's where we draw our view on that matter."
She added: "Certainly the evidence with regard to the British Association of Perinatal Medicine is pointing quite clearly to the point that viability, whatever the vast improvements, and there are significant improvements, cannot be continually pushed back in terms of a date."
Arguments have raged around the definition of viability, with some arguing it simply means being born alive, and others claiming it requires the baby to have a meaningful life.
Last night, a spokeswoman for the ProLife Alliance claimed the birth three weeks ago of Graiden Eldred, at just under 24 weeks, should force legislators to look at dropping the limit.
She said: "It is almost as if there is an absolute reluctance to give any leeway to the unborn child.
"That's the feeling - that they are not going to want to budge on [the issue] that there might be something wrong with aborting babies at 24 weeks. I think most public opinion is opposed to abortion at that stage."
But Anthony Ozimic, political secretary of the Society for the Protection of Unborn Children, said: "We are pleased that the government does not seem interested in seeing the Abortion Act amended at this time.
"Any amendments to the Abortion Act at this time are likely to result in an increase in the numbers of abortions.
"We call upon parliamentarians to resist calls, from whatever quarter, to table amendments to the Abortion Act and instead to focus upon the many practical ways of reducing the numbers of abortions, in particular by addressing the pressures upon expectant mothers which lead them to consider abortion."
At a later press conference, held as part of the Voice for Choice campaign, MP Emily Thornberry, vice-chairwoman of the all-party parliamentary pro-choice and sexual health group, said the committee had been wrongly convinced they should look at whether there had been a medical breakthrough on foetal viability. She said there had been no such breakthrough.
"Instead of using the opportunity of the 40th anniversary to celebrate the fact that there has been an abortion law in Britain over 40 years, we are finding ourselves defending what we have," she said.
And Anne Quesney, director of Abortion Rights, said later-stage abortions were rare and were needed by women facing "extraordinarily difficult circumstances".
She said the tactic of focusing on later abortions was part of the anti-choice lobby's "step by step" approach to their ultimate goal of making all abortion illegal.
Voice for Choice, a group of 13 pro-choice organisations seeking reforms to the act, has an agenda that includes making abortion available solely at the request of the pregnant woman within existing time limits.
A Department of Health spokeswoman said last night: "We are on the record as saying there are no current plans to change the rules on abortion but further than that we are not able to say."
The debate raged on the eve of a protest at Holyrood by the newly formed Women's Abortion Rights Scotland.
The move, as revealed by The Scotsman last weekend, is a direct response to First Minister Alex Salmond's recent comments on the issue, and his personal support for a reduction in the time limit to 20 weeks.
• Abortion was outlawed in 1803 - and made punishable by death - following protests from doctors concerned that it was regularly carried out by non-medical personnel.
• The 1967 act clarified the issue, allowing for legal abortion on a number of grounds, with the added protection of free provision through the NHS.
The act set a general time limit of 28 weeks, and required that the procedure must be certified by two doctors.
• The Act does not apply to Northern Ireland, where it is still illegal to carry out abortions.
• Medical advances have since brought about changes in the time limit, which was reduced to 24 weeks under the Human Fertilisation and Embryology Act 1990.
• In Scotland, the number of abortions has risen from 11,997 in 2000 to 13,081 last year,
• including 362 carried out on girls under the age of 16.
• Scots considered to be socially deprived have consistently had the most abortions during the past decade representing almost 30 per cent of procedures. Last year the most affluent accounted for just 14 per cent.
• More than nine-in-ten of abortions in Scotland over the past decade were carried out before 13 weeks.
• A Mori poll in 2006 showed support for tightening of laws on abortion. A total of 42 per cent of those questioned believed that the legal limit should be cut. However, just 10 per cent of women wanted abortion "outlawed altogether".
• The Church of Scotland has said that while in the great majority of cases abortion has no moral justification, it can only be sustained where it risks the life or health of the mother; a case of rape or incest has been proven; or where it is known the foetus is damaged or deformed.
• Women can refer themselves for private abortions, which start from around 450 and increase to 750 or more in the later stages of pregnancy.
• There are two methods of early abortion. One involves two tablets which once ingested end the pregnancy within four hours and can be used in the first nine weeks of pregnancy.
The second , "vacuum aspiration" , is used up to 13 weeks and involves the insertion of a tube into the womb and removal of the foetus by suction.
A SET of twins has become the first babies in Britain to be artificially conceived using a revolutionary procedure that dispenses with fertility drugs.
The children, who are not being named, were created by IVM - in vitro maturation - which involves extracting dormant eggs from the ovaries and maturing them in a laboratory. The technique is safer, faster and cheaper than in vitro fertilisation (IVF) as no drug treatment is required prior to collecting the eggs.
A key advantage is that it avoids the possibility of dangerous side-effects that can occur if the ovaries are over-stimulated.
However, only about 400 IVM babies have been born worldwide, compared with about two million IVF babies.
In January, the private Oxford Fertility Unit became the first IVF clinic in the UK to be awarded a licence by the Human Fertilisation and Embryology Authority to offer the treatment.
Yesterday, the clinic announced the birth of the twins. They were delivered one minute apart last Thursday and are said to be doing well. The boy weighed 6lb 5oz; his sister, 5lb 14 oz.