Down’s Syndrome numbers don’t add up

November 24, 2008

Are more women choosing to have a Down’s Syndrome baby despite learning from a prenatal scan they are carrying a child with the condition?

The Down’s Syndrome Association charity believes this is the case. Its conclusion has been widely followed in press reports, including in the Daily Mail, Independent and the Times.

But research data published in response by the National Down Syndrome Cytogenetic Register (NDSCR) in London suggests otherwise. It says that the rate of terminations of unborn Down’s Syndrome babies has remained constant since prenatal screening became widely available in 1989.

The Down’s Syndrome Association says its help desk has been receiving an average of two calls a week from expectant mothers who have received a positive scan for the condition who say they are continuing their pregnancy, a much higher rate than two to three years ago.

And it points to figures from the NDSCR showing that more Down’s Syndrome babies are now being born in England and Wales than before the start of widespread prenatal screening — there were 749 births in 2006, the latest year figures are available, compared to 717 in 1989 and a low of 563 in 1995.

The number of Down’s Syndrome births as a proportion of all live births has also increased by around 15 percent since 2000.

Carol Boys, the chief executive of the Down’s Syndrome Association said in a press release she was surprised by the numbers.

“It seems to show that more parents are thinking more carefully before opting for prenatal screening and termination –- that being born with Down’s syndrome is being seen in a different light today.”

Together with the BBC, the Association conducted a survey of parents of children with the condition to find out “why more women are opting to go ahead with their pregnancies”.

The findings suggest that attitudes to people with the condition or other disabilities have changed for the positive. Some 35 percent of the parents asked said they felt life and society had improved for people with Down’s Syndrome.

But an examination of birth and termination data cited by the Association and compiled by the NDSCR fails to show that more mothers are indeed pressing on with their pregnancies.

NDSCR Research Director Professor Joan Morris, based at the Wolfson Institute of Preventive Medicine in London, told me she had issued a release of her own in response to the charity’s claim.

The release says: “92 percent of women who receive an antenatal diagnosis of Down’s syndrome decide to terminate the pregnancy. This proportion has not changed since 1989.”

“I’m pretty annoyed with the Down’s Syndrome Association that seem to have totally the wrong end of the stick,” she said.

“The story as we see it is massive increases in the number of Down’s Syndrome pregnancies, due to maternal age increasing, and a lot more screening going on.

“That is causing a lot of the pregnancies to be diagnosed prenatally and women decide to have terminations.

“These two big increases are matching against themselves … and the end result is that the number of births is increasing very slightly. But it’s nothing to do with women deciding to keep their pregnancies.”

[Picture shows Down's Syndrome performer Hu Yizhou from the China Disabled Peoples Performing Art Troupe conducting at a rehearsal for a concert in Seoul in this March 2004 photo. REUTERS/You Sung-Ho]

One comment

We welcome comments that advance the story through relevant opinion, anecdotes, links and data. If you see a comment that you believe is irrelevant or inappropriate, you can flag it to our editors by using the report abuse links. Views expressed in the comments do not represent those of Reuters. For more information on our comment policy, see http://blogs.reuters.com/fulldisclosure/2010/09/27/toward-a-more-thoughtful-conversation-on-stories/

I am interested to see the NDSCR figures produced in response to this highly publicised DSA survey.A further element that particularly concerns me is the figure, variously reported online as ´almost a fifth´ or ´almost a half´ of those questioned who cited ´thinking that the baby was not going to have Down syndrome´ as a reason to continue with the pregnancy. Whilst this many be a manifestion of denial, which may be a potent component of coping with such a situation, surely this raises a major question about the degree/effectiveness of counselling that these women and their partners received?For pregnancies that had had cytogenetic confirmation of trisomy 21 (by amniocentesis, for example), the chances of the baby not having trisomy 21, i.e. Down syndrome, were exceptionally small indeed. (In contrast, in the case of people who chose not to have any invasive prenatal testing, where the likelihood of Down syndrome was suggested on scan findings only, there would indeed still have been significant uncertainty.)Down syndrome conception rates are higher as more women over the age of 35 are having children. These higher numbers of people requiring counselling in a pregnancy likely to be affected by Down syndrome must be addressed at a population level.The DSA´s view that Down syndrome is not an indication for termination of pregnancy is entirely in keeping with their purpose of promoting the rights and aspirations of people with Down syndrome and their families. Lobbying for appropriate counselling to be available for every pregnancy in which Down syndrome is suspected is compatible with this, and therefore it seems that this should be a priority area.

Posted by anonymous geneticist | Report as abusive