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The Whole Truth

Down's syndrome

For every 660 Down’s syndrome foetuses that are detected and terminated in the UK each year, 400 normal children perish as well.

By Michael Cook

A blood test for Down’s syndrome claims to be the “Holy Grail” of prenatal testing.

If you are ever searching for bioethics case studies, it’s hard to go past the Daily Mail, Britain’s number-two tabloid. It’s not all saucy tittle-tattle about the glam set and the royals: human interest is what drives the Daily Mail, and there are no more poignant stories than birth and death, the great themes of bioethics.

So I was taken aback recently when I read a long feature about prenatal testing. “A quick inexpensive blood test for Down’s syndrome that could save the lives of hundreds of unborn babies each year is being developed by scientists,” a report read. Prof Stephen Robson, a spokesman for the Royal College of Obstetrics and Gynaecology, even described it for the Daily Mail’s readers as the “Holy Grail” of prenatal testing.

Now there are many contending theories of bioethics, but every author would agree that a commitment to the unvarnished truth is a founding principle. And what the Daily Mail told its readers, on the authority of the venerable RCOG, is what we might call a thickly varnished truth: the lives of unaffected babies are “saved” only in the sense that they would not be miscarried as a result of invasive investigations to search out and destroy Down’s syndrome babies.

This is what happens. The vast majority of positive blood tests for Down’s syndrome are false. But to confirm the diagnosis, worried mothers have an amniocentesis, a test in which amniotic fluid is extracted with a long needle. Or, earlier in the pregnancy, they can have chorionic villus sampling, in which a sample of placental tissue is taken. Approximately 1–2% of foetuses tested miscarry.

According to a report in the Down’s Syndrome Research and Practice journal in 2008, the upshot of this is that for every 660 Down’s syndrome foetuses that are detected and terminated in the UK each year, 400 normal children perish as well. The proportion is much the same in Australia.

So there are two sides to Prof Robson’s Holy Grail: saving the lives of the 400 normal children and taking the lives of 660 Down’s syndrome children. And this number is bound to grow. Because the average age of pregnant women is rising there will be a “massive increase” in Down’s syndrome pregnancies, according to Lachlan de Crespigny, an Australian expert on prenatal testing.

At the moment, about 92% of women in advanced countries abort a Down’s syndrome child after it has been detected. A Harvard Medical School expert on Down’s syndrome children, Dr Brian Skotko, even predicts that they could become “extinct”, especially after the “Holy Grail” of a non-invasive test is discovered.

A 3:2 kill ratio is a very high rate of collateral damage. Even in a Chuck Norris film it would be unacceptable. Are Down’s syndrome children really so dangerous that normal children have to perish so that they can be eradicated? Is it really true that they will ruin your life?

Not according to Dr Skotko. Most doctors, he reported in the Archives of Disease in Childhood last year, know very little about life with Down’s syndrome and put subtle or not-so-subtle pressure on pregnant women to abort affected foetuses. Many women told him that their physicians had provided them with incomplete, inaccurate and often offensive information about the condition. He found that women were being told that Down’s syndrome was too great a burden for the child to bear.

However, this is not the experience of many parents. Despite significant health problems, Down’s syndrome children have a placid, loving disposition that often brings much consolation to parents. Some parents even say that their Down’s syndrome child is easier to raise than their other children. As Skotko puts it: “Parents who have children with DS have already found much richness in life with an extra chromosome”.

The problem is that medical students and doctors know very little about people with intellectual disabilities. A recent study in the Journal of the American Medical Association found that “many physicians are ill-prepared to recognize symptoms or appropriately examine patients who have the physical limitations, communication difficulties, or behavioral issues that often coexist in persons with [intellectual disability]”.

Reproductive rights is an inflammatory issue, but surely women deserve to be told the whole truth. Only then do they have a real choice.

Michael Cook is editor of BioEdge, an internet bioethics newsletter.