A small change in the testing procedure for gestational diabetes has increased the reliability of the results, researchers from the Australian National University have found.
The process for testing gestational diabetes involves eight hours of fasting before a blood sample is taken.
The patient then drinks a glucose drink before another blood sample is taken, they wait an hour and give blood again.
Those blood samples are then processed.
A study of more than 12,000 women has found that processing the blood samples earlier produced “substantially higher” rates of positive diagnosis for gestational diabetes – from 11.6% to 20.6%.
ANU lead researcher Professor Christopher Nolan said the blood samples continued using glucose as they waited and therefore might produce an incorrect result.
He said this was a particularly problematic for women in regional areas.
“Women in the country might take the test in their GP’s office and it might wait until later in the day to be picked up by a courier,” he said.
“They are in the highest risk of not being diagnosed.”
Professor Nolan said the testing inconsistency was a “real problem” in many countries around the world and action needed to be taken.
“Women deserve accurate test results,” he said.
Professor Nolan said an easy fix would be to change the chemicals in the blood test collection tubes from sodium fluoride to citrate.
He said his research highlights the importance of the pre-analytical processing protocol and urges that more research is needed before adopting citrate tubes widely. He has been in contact with the Australian Association of Clinical Biochemists (AACB) and hoped his research would inform their testing procedures.
“A few members of the AACB are taking this very seriously,” he said. “We want to sort this out.”
