New hope for prem babies
Blood test being developed in Auckland could save thousands of lives worldwide
Auckland researchers are developing a blood test to predict premature birth, a ground-breaking move that could save thousands of lives around the world each year.
At present there is no simple screening test to find out if a woman might spontaneously go into labour too soon. The potential new test could enable the targeting of therapies that could delay or even prevent some premature births.
The research team from Auckland University’s Medical School and Liggins Institute have struck success in a small study with blood samples taken from 24 women at 20 weeks into their first pregnancy.
They found a unique molecular fingerprint in blood taken from women at 20 weeks of pregnancy who all went on to have their babies early.
The fingerprint was not present in blood taken from women who went on to deliver at term.
“We are very excited with the preliminary results,” said study coleader Professor Lesley McCowan, a maternal and fetal medicine specialist.
Globally, about 10 per cent of births are premature — before 37 weeks. In New Zealand the figure is about 8 to 9 per cent — more than 5000 babies a year.
Around 60 per cent of premature births occur spontaneously, often in women with no prior history or warning.
The remainder have an induced labour, a planned caesarean or an emergency caesarean before the onset of labour.
The deaths of about 50 newborns and 25 stillborn deliveries a year are attributed to spontaneous premature birth in New Zealand.
Premature birth carries numerous health risks, including vision and hearing problems, cerebral palsy, learning and development difficulties and, in adult life, obesity and diabetes. The earlier a baby is born, the greater the risks; few survive if born earlier than 24 weeks.
“If we can develop a reliable blood test to identify women who will have a spontaneous preterm birth by midpregnancy,” McCowan said, “this has potential to lead to a huge advance in clinical practice.”
Women identified by the test could be referred to specialist clinics
that already exist for those known to be high risk for preterm birth because of factors such as having had a previous premature baby.
Tests for preterm birth can be done on women at risk, such as measuring the length of the cervix and vaginal swabs.
Treatments are available — depending on each woman’s circumstances — such as placing a suture around or through the cervix to clamp it shut, or progesterone hormone therapy. They can delay the onset of labour, but are not considered 100 per cent guaranteed.
The potential biomarker found in the pilot study was derived from analysis of women’s micro-RNA. These are RNA molecules that play key roles in the regulation of gene expression.
They are involved in development of, and protection from, various diseases.
Micro-RNA “fingerprints” have also been identified as potential markers for the weak-bone condition osteoporosis, cancers and the preg- nancy complication pre-eclampsia.
Having identified the preterm birth biomarker, the Auckland University researchers are now doing a larger study to confirm their results. Like the pilot study, it is based on blood samples given by more than 2000 women in their first pregnancy in a series of studies that began in 2004.
The new study will include results from blood tests at 15 weeks into pregnancy.
McCowan said that if they proved predictive like the 20-week findings, this would be “even more exciting, because there’s greater potential to try to modify things”.
The research began with a grant from the Auckland Medical Research Foundation.
Now the Auckland Harbourside Rotary Club will donate money raised at its Chinese New Year ball on Saturday at SkyCity.