Australian doctor wants all pregnancies there tested for Down syndrome

From The Sydney Morning Herald in Australia:

Australia urgently needs a national screening policy for Down syndrome, experts say, after international research showed it could halve the number of babies born with the incurable genetic condition.

Access to the four tests that help detect if a foetus has Down syndrome varies widely between states, urban and rural areas, and public and private patients, leading to stark differences in birth and termination rates.

A Danish study published in the British Medical Journal last week showed a national screening program for expectant mothers halved the number of babies born with Down syndrome in Denmark. The number of babies diagnosed with the syndrome before birth increased by 30percent and there were fewer false positives.

Euan Wallace, professor of obstetrics at Monash University, said: "In Australia in 2008 every single woman should be offered and have access to state-of-the-art screening tests irrespective of age."

The Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG) agrees, saying two screening tests - ultrasound nuchal translucency measurement and serum screening - have a combined detection rate of 90 percent.

But in NSW, free screening tests are available in public hospital antenatal clinics only to women aged 35 or over or with a family history of chromosomal defects.

Down syndrome, also known as trisomy 21, occurs in about 2.5 of every 1000 pregnancies. Although the risk increases with maternal age, about half of occurrences are in mothers under 35, as about 80percent of all mothers are in this age group.

Professor Wallace said NSW Health's age-based policy is "15 years out of date and not good public health policy". Dr Amanda Sampson from RANZCOG said women under the care of a private obstetrician can choose to pay for testing, and the introduction of Medicare rebates had seen the number of private tests skyrocket.

A study of births in Queensland between 2000 and 2004 published in The Medical Journal Of Australia last year found the incidence of Down syndrome was 56 percent higher for mothers in the public hospital system than those treated by a private obstetrician, presumably because higher income gave access to better-quality testing.

The study also found rural women had a 34percent higher risk of having a Down syndrome baby compared with city-dwelling women. "There's enormous variation, in practice, from state-of-the-art high-quality screening services to nothing much at all and with a persistent vacuum of national policy this is not going to change," Professor Wallace said.

Jill O'Connor, from Down Syndrome NSW, said the number of women who missed out on screening because they couldn't afford it was unknown.

Denmark conducted a combined test based on maternal age, serum and nuchal screening in the first trimester in 2004. The number of infants born with Down syndrome reduced from 55 to 65percent a year in 2000-04 to 32percent in 2006. Eight out of 10 expectant mothers opted for screening.