New screening halves the number of children born with Down syndrome

Nov 28, 2008

A new national screening strategy in Denmark has halved the number of infants born with Down's syndrome and increased the number of infants diagnosed before birth by 30%, according to a study published on bmj.com today.

Many countries, including England, Australia and New Zealand, are trying to introduce national screening strategies for Down's syndrome, but are facing a variety of problems because of a lack of consensus about the screening policy and logistical challenges.

In 2004, the Danish National Board of Health issued new guidelines for prenatal screening and diagnosis. These included the offer of a combined test for Down's syndrome (based on combination of maternal age, plus serum and nuchal screening) in the first trimester. This test gave women a risk assessment for Down's syndrome at an early stage in the pregnancy. Women whose risk was higher than a defined cut off were referred for invasive diagnostic tests (chorionic villus sampling or amniocentesis).

In the previous guidelines screening for Down's syndrome was based on maternal age and a diagnostic test was mainly offered to women above 35 years.

Professor Ann Tabor and colleagues from Denmark, evaluated the impact of the new national screening strategy on the number of infants born with Down's syndrome and the number of referrals for invasive procedures. They analysed data from the 19 Danish departments of gynaecology and obstetrics and the national cytogenetic registry, for an average of 65,000 births each year, between 2000 and 2007.

Uptake was good, by June 2006 all 15 Danish counties followed the guidelines from 2004 and offered the new screening strategy. In 2006 approximately 84% of pregnant women had a risk assessment for Down's syndrome.

The researchers found that the new strategy was associated with improved earlier detection of Down's syndrome, low false positive rates, and more than a 50% decrease in the number of invasive tests carried out each year.

They report that the number of infants born with Down's syndrome decreased from 55󈞭 per year during 2000𔃂, to 31 in 2005 and 32 in 2006. The total number of invasive tests fell sharply from 7524 in 2000 to 3510 in 2006.

The detection rate in the screened population was 86% in 2005 and 93% in 2006. With 3.9% (17) of women receiving a false positive result in 2005 and 3.3% (7) in 2006.

The authors point out that the value of this new screening strategy is that all women can be assessed early in pregnancy (in the first trimester). The national guidelines emphasise that risk assessment should only be done if women choose the test on the basis of informed choice, therefore despite the programme being available to all pregnant in women in Denmark, some will still choose not to be screened.

The authors conclude by emphasising Denmark's success at building a strong national organisation for fetal medicine and a national quality database that allows follow-up of all screened women at a national level and quality control of the new national screening programme.

Source: British Medical Journal

Explore further: Sierra Leone faces criticism over Ebola shutdown

add to favorites email to friend print save as pdf

Related Stories

New defense mechanism against viruses discovered

Sep 11, 2014

Researchers have discovered that a known quality control mechanism in human, animal and plant cells is active against viruses. They think it might represent one of the oldest defense mechanisms against viruses ...

Lab unveil new nano-sized synthetic scaffolding technique

Sep 02, 2014

Scientists, including University of Oregon chemist Geraldine Richmond, have tapped oil and water to create scaffolds of self-assembling, synthetic proteins called peptoid nanosheets that mimic complex biological ...

Mysteries of space dust revealed

Aug 29, 2014

The first analysis of space dust collected by a special collector onboard NASA's Stardust mission and sent back to Earth for study in 2006 suggests the tiny specks open a door to studying the origins of the ...

Recommended for you

Sierra Leone faces criticism over Ebola shutdown

4 hours ago

Sierra Leone began the second day of a 72-hour nationwide shutdown aimed at containing the spread of the deadly Ebola virus on Saturday amid criticism that the action was a poorly planned publicity stunt.

Presence of peers ups health workers' hand hygiene

18 hours ago

(HealthDay)—The presence of other health care workers improves hand hygiene adherence, according to a study published in the October issue of Infection Control and Hospital Epidemiology.

Sierra Leone streets deserted as shutdown begins

Sep 19, 2014

Sierra Leone's normally chaotic capital resembled a ghost town on Friday as residents were confined to their homes for the start of a three-day lockdown aimed at halting the deadly Ebola epidemic.

Sierra Leone launches controversial Ebola shutdown

Sep 19, 2014

Sierra Leone on Friday launched a controversial three-day shutdown to contain the deadly spread of the Ebola virus, as the UN Security Council declared the deadly outbreak a threat to world peace.

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

weewilly
not rated yet Nov 29, 2008
So I suppose that what this article did not bring out is that all who tested positive or at least the majority of them who did, had abortions. Amazing science that gives the freedom of choice a push into immorality. Hitler and a few others tried to make that choice too.