Bland statistics usually conceal personal dramas, even tragedies. So it is with the statistics on Down's syndrome diagnosis. Many more women are being told they are carrying a baby with Down's syndrome: a 71% increase in diagnoses over the last 20 years. The proportion of prospective parents opting for termination remains constant, at just over 90%.
Like most people, perhaps, I support a woman's right to choose, and I support the right to have information about pregnancy, and I support the right of those who cannot face parenting a child with Down's syndrome to opt for termination. But those bland statements do not mean that we cannot have concerns over the human cost of the UK screening programme. I believe that the headline figures need a little unpacking, in order to understand some of their implications for real people.
One reason for the increase in diagnoses is the extension of maternal serum screening to all women, rather than only women over the age of 35, who are at greater risk. As a consequence, the proportion of fetuses with Down's syndrome detected in younger mothers has risen from 3% to 43%. But the extension of screening also means more anxiety for more women, the vast majority of whom will not be carrying a Down's syndrome fetus. Even among those who screen positive and go on to a diagnostic test, 95% will be found to be carrying a non-affected baby.
Research last year by Frank and Sue Buckley estimated that to prevent the birth of 660 Down's syndrome babies, 400 healthy pregnancies would miscarry. This is because the diagnostic tests – amniocentesis or chorionic villus sampling – each carry a risk of miscarriage of about 1%: tiny, but when vast numbers get screened, this risk results in the tragic toll of about 1,000 miscarriages caused by the diagnostic process. We need more research into the feelings of those who experience these iatrogenic miscarriages.
To the distress of those wanted pregnancies that fail as a result of screening interventions must be added the complicated feelings of the 1,695 couples who received a positive diagnosis and opt for termination. These are not early terminations of unwanted pregnancies, which are generally simpler to perform, and perhaps more straightfoward – though clearly still distressing – for most women. These are terminations of wanted pregnancies around 18-20 weeks, in other words, around the same time as the first movements of the developing baby are felt. We need more research into the long-term emotional consequences of these difficult decisions.
Human reproduction has a natural tendency to screen out anomalies, and therefore even without intervention, many pregnancies affected by Down's syndrome would spontaneously terminate. In other words, for a proportion of those who opt for diagnosis and termination, they are assuming responsibility for something that would have happened naturally anyway. It would be relevant to investigate whether the distress at a spontaneous miscarriage is less than the distress at having to make the active choice of termination.
The major reason for the increase in diagnoses, of course, is the decision of many women to delay becoming mothers. It is well known that older women have a higher risk of having Down's syndrome-affected pregnancies or fertility problems. Our social or cultural choices are making us more dependent on medical intervention, and at higher risk of morally and emotionally burdensome choices.
It must be particularly poignant for women who have struggled to become pregnant, then to be faced with the prospect of choosing to terminate that desperately wanted pregnancy because they cannot face bringing up a child with Down's syndrome. It is evident that some older women decline the choice of screening, because they would prefer to have a Down's syndrome baby than no baby at all.
I have long felt that it is a priority to provide better information to prospective parents about what Down's syndrome is, and the effect it has on individuals and their families. Some years ago, my team produced a website to do just that, including photographs and interviews with people with Down's syndrome and their parents. Our pilot initiative was never taken up or developed by the NHS, or those who are so keen to produce ever better screening or diagnostic tests, although Health Talk Online did some excellent work interviewing couples who had undergone screening in pregnancy: I believe as much money should be spent on information and counselling as is spent on the technology, because humans matter more than statistics and cost/impact calculations.
Within the next 10 years, we will have better tests for fetal anomalies that will be non-invasive and performed early in pregnancy, thus reducing the risk of miscarriage, and perhaps lessening the emotional burden of later termination. But until these tests enter clinical practice, thousands of families face difficult decisions and long-term emotional consequences as a result of our increased scientific capabilities and our societal trends in parenting.
