Unequal access to antenatal screening could be one of the reasons why Down syndrome births are higher in rural than urban areas of Queensland, according to senior Queensland health analysts.
Michael Coory, of the University of Queensland, and Timothy Roselli and Heidi Carroll, of Queensland Health, examined the births of babies with Down syndrome in Queensland to see whether the mother's place of residence and type of antenatal care had any impact.
Their results, published in the latest Medical Journal of Australia, show that since 2000 there has been a fall in the rate of Down syndrome births to mothers who live in urban areas, but not to mothers who live in rural areas.
The authors say that possible reasons for higher rates in rural areas include unequal access to screening and confusion about screening guidelines and protocols.
Several expert groups, including the Australian and New Zealand College Obstetrics & Gynaecology, now recommend population-based Down-syndrome screening - that is, screening for all expectant mothers, regardless of age.
Recommended screening involves ultrasound and blood tests early in the pregnancy. In the past, screening was only offered to mothers older than 35 years.
"Accurate ultrasound testing for Down syndrome requires properly trained operators with good ultrasound machines," say the authors.
"These are in short supply, and this, along with the need for quality control, means that ultrasound screening services are confined to urban centres.
"However, recent advances in antenatal blood tests mean that rural women could be screened without using ultrasound.
"Economic analyses have shown that population-based screening probably represents value for money. . . When the costs of screening are offset against the lifetime costs of caring for a person with Down syndrome, screening is less costly than no screening at all."
Some expectant parents will not want to take up an offer of screening because a confirmed positive result means that they would be faced with the dilemma about whether to have a termination.
"All expectant parents should be provided with the same information and have the same access to services so that they all have the same choices," say the authors.