Boy, it’s going to be one hell of a bunfight on College Green on Tuesday. It’s shaping up to be just like the old days. Well, almost. Not only will there be a mass protest vigil from the We Can crowd from west London (short for “Mummies and Labradors Against the Third Runway”), protesting against airport expansion, but they’ll be joined by the clashing demos of pro-lifers and pro-choicers, all duking it out for lebensraum and media attention, while inside the relative calm of the Palace of Westminster, lucky MPs get a free vote regarding the upper time limit governing abortions.

So why are we here again? Well, it’s because the Human Fertilisation and Embryology Bill is being steered through parliament, and this offers MPs a chance to amend the 1967 Abortion Act, a chance that many of them have taken: after all, we have seen those blissed-out, moving pictures of foetuses sucking thumbs or appearing to walk in the womb, and we have all heard shocking statements from doctors who describe terminations of 24-week-old foetuses taking place in one part of a hospital, while neonatologists struggle to save a premature baby of exactly the same term in another, both of which raise the question: at 24 weeks, is the legal time limit of abortion too high (it was cut from 28 weeks in 1990)? And is there a case for lowering it in line with other European countries, such as Spain, and the Netherlands, that have opted for a less savage-sounding 22 weeks on the grounds that some babies can and do survive from 23 and 24 weeks.

Lots of MPs think there is grounds for a change in the law, led by Nadine Dorries, and followed by David Cameron and others. At the time of writing, many MPs have tabled a wide range of amendments proposing a reduction in the abortion time limit of 24 weeks: amendments 1-5 and 9 variously propose reductions to 12, 14, 16, 18, 20 and 22 weeks in the time limit, in a slightly dubious display of parliamentary spread betting.

Amendment 6 seeks to ban “termination of pregnancy on the grounds of the disability, gender, race or sexual orientation of the child”. Amendment 7 seeks to impose on doctors the burden of offering counselling, providing the pregnant woman with two-weekly updates on foetal development, info on the physical, psychological and psychiatric risks associated with abortion, and adoption services, and the imposition of a fat fine if they don’t oblige.

Some of these amendments – such as the one that tells docs to spell out the possible traumatic aftershock, or the one suggesting a cooling-off period between asking and getting the procedure, sound sensible, especially given the fact that there is an increased risk of suicide and breakdown in women after abortion.

So why not, after all, lower the time limit to 22 weeks, given that we do read of “miracle babies” that do pull through, against the odds, when they are delivered at less than the legal time limit of abortion of 24 weeks? The last time I wrote about this subject, I received many kind letters, telling me that I shouldn’t say “abortion” but “the deliberate killing of an unborn child”, and suggesting I should be made to stand and watch as a foetus’s brain was sucked out of its skull, or dismembered alive before being withdrawn via the birth canal, and so forth, which I found odd, to say the least.

It always puzzles me that these evangelists for the unborn can expend so much energy on the preservation of the zygote or the foetus at the very beginning of its earthly existence, but are conspicuously silent about the fact that at the end of precious, sacred, holy life, the old and the dying are left to sit in their own pee in care homes in front of Emmerdale.

But here we go, anyway. Obviously, I hate the idea of babies being ripped out of wombs and destroyed when they have the chance of life. But I am not a neonatologist. All I can do is report the science and technology committee, that reviewed all the evidence, the nationwide EPICure 2 survey, and the Trent region survey published and endorsed by the British Medical Journal, that showed no improvement in survival of those born before 24 weeks over the past 12 years. All the above concluded that – despite the occasional, heart-warming story of miracle babies making it against all the odds, the evidence is that very few babies younger than 23 weeks survive, and claims that the lives of as many as 2,000 babies a year could be saved by a reduction in the limit to 20 weeks are simply not borne out by the facts.

The experts also say that those who table amendments seeking lower time limits will only raise the hopes of those whose premature babies are sadly not going to survive. Professor David Field, the professor of neonatal research who led the Trent survey, says of the pro-life MPs: “These people have chosen to muddy the waters, and try to change people’s expectations that babies are viable at 23 weeks. They’re not. You can legislate all you like, but you can’t change what nature means to do.”

So, after much research and talking to doctors and MPs, I agree with the experts. Keeping the 24-week threshold will uphold, rather than restrict, a woman’s rights over her own body and own reproductive destiny. I am – along with Gordon Brown, three-quarters of the population, including most unions, the Family Planning Association and the British Medical Association – in favour of leaving the law as it stands. Those terminations carried out at the outer limit of the law are very rarely what we call social abortions, and the number of them is tiny – compared with the number of abortions overall, which is too high, but that’s another column.

Almost all – 90% – of abortions are done within the first trimester. A fraction – only 2% – are done after 20 weeks, and these are the abortions that are needed most: by young girls who didn’t know they were pregnant, by women with abusive partners, by rape victims, by postmenopausal women, by women whose foetuses are gravely impaired. After 22 weeks, the abortion rate is less than 1%.

Women don’t have terminations at five months because they suddenly want to get into a pair of white skinny jeans; they do so because they are desperate.

The Abortion Act has protected women at their most vulnerable for 40 years. Yes, abortion is a matter of life and death, but it is, above all, a health procedure that is best left to the discretion of the doctor and patient.

And it’s much too important to be left to the extremists, either inside parliament, or outside on College Green.

rachel.johnson@sunday-times.co.uk

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