Fetal oxygenation study (FOX)

Fetal oxygenation study (FOX)

Each year, stillbirth claims the lives of thousands of babies before they ever take their first breath. Many of these losses are preceded by a long, silent period of dwindling oxygen supply that slows the baby's growth inside the womb. If we had a test to detect declining oxygen levels before a baby becomes critically ill, we could save many young lives.

Severe preterm fetal growth restriction – babies at highest risk of stillbirth

Severe reductions in nutrient and oxygen supply can slow the growth of a baby before 34 weeks of pregnancy. This is usually due to a poorly functioning placenta, rather than the diet or health of the mother. This condition - called preterm fetal growth restriction - is a very severe disease that carries a high risk of stillbirth if the baby is is not born well before the pregnancy due date.

When a fetus has slowed its growth in mid pregnancy because of severely reduced oxygen supply, there are difficult decisions to make. On one hand, giving birth to a baby that is very small and immature can lead to death after birth or serious long term health problems for the infant. On the other hand, continuing a pregnancy as long as possible to maximise the baby's maturity and size carries a substantial risk of the baby dying before birth.

Fetal medicine specialists use a number of tools to try to get the balance right - the balance between delivering a small, sick baby too early, or too late.  We use ultrasound to monitor the baby's blood flow, growth rate, amniotic fluid levels and activity inside the womb. We also regularly check the baby's heart rate patterns and movements with an external fetal heart rate monitor.

Although valuable, these measures are imperfect and tragically, we do not get the balance right every time. There is an urgent need for more accurate ways to assess the baby's oxygenation so we can plan birth at the best possible time for these critically ill babies.

A blood test to identify fetuses with very low oxygen supplies

The FOX study aims to develop a new maternal blood test to identify unborn babies with dangerously low levels of oxygen.

This project is based on important discoveries made by Mercy Perinatal researchers. We have discovered particular molecules (RNA) that are released from the placenta into the mother's bloodstream when the baby is suffering from very low oxygen levels.  We intend to measure these molecules in a large group of women who have preterm fetal growth restriction to see if these molecules can give us useful information about the timing of birth.

Fortunately, preterm fetal growth restriction is rare. But because it is rare, we need our specialist colleagues around Australia and New Zealand to help us in our research. We are immensely grateful that six major hospitals in Victoria, New South Wales, Queensland and Auckland have joined us in this mission to improve our care for these very vulnerable pregnancies.

Where is the FOX study up to now?

We have collected blood samples from more than 120 women with preterm fetal growth restriction and 84 women with normal pregnancies. We are very pleased to report that the Australian Genomic Research Facility has commenced analysis of these samples using the latest "next generation" technologies (RNA-sequencing). We believe that the FOX study is well on the way to providing answers that will help us bring mothers and babies safely home.

The FOX team

Chief Investigators

Professor Stephen Tong
Professor Sue Walker
Dr Clare Whitehead
Dr Natalie Hannan
A/Prof Joanne Said (University of Melbourne)

Our Australian and New Zealand collaborators

A/ Professor Joanne Said, Western Hospital, Sunshine, Melbourne
Dr Stefan Kane, Royal Women’s Hospital, Melbourne
Dr Sean Seeho, Royal North Shore Hospital, Sydney
Dr Scott Peterson, Mater Mother’s Hospital, Brisbane
Dr Katie Groom, National Women’s Health, Auckland City Hospital
Dr Amanda Henry, Royal Hospital for Women, Sydney

PhD Student

Dr Owen Stock

Research Midwife

Gabrielle Pell

Research Assistants

Sally Beard
Natalie Binder

Bioinformatics consultant

Lavinia Gordon

Our financial supporters

We are very grateful to our many supporters, including:

National Health and Medical Research Council of Australia
RANZCOG Research Foundation
The Norman Beischer Medical Research Foundation