Fetal longitudinal assessment of growth study (FLAG)

Fetal longitudinal assessment of growth study (FLAG)

As a pregnancy advances past 38 weeks gestation, the risk of stillbirth slowly rises. This risk is even higher if the fetus has impaired growth due to placental insufficiency. Better detection of fetal growth restriction at term could prevent many cases of stillbirth by identifying those that would benefit from planned timing of birth.

We know that the traditional methods of identifying small babies using the tape measure and physical examination of the woman’s abdomen misses more than two thirds of all growth restricted babies.  Even performing ultrasound on all pregnant women in late pregnancy detects just over half of small babies.

The FLAG study team aspires to develop a novel blood test to better identify term babies that are small, since these babies are at increased risk of stillbirth. We will also look for new ultrasound markers of impaired growth to use either alone, or in combination with a blood test, to improve detection of placental insufficiency.

What does the FLAG study involve?

Part A of the FLAG study involves collecting blood samples from pregnant women to measure molecules released by the placenta that are detectable in the bloodstream (‘placental RNA’). This blood test will be performed on 2000 women at 28 weeks and 36 weeks to see if fetal growth restriction produces a characteristic placental RNA signature in the blood.

If we discover a placental ‘signature’ that reliably predicts babies that are destined to be growth restricted at term, this blood test could be used to allow planned delivery before stillbirth occurs.

Part B of the FLAG study involves serial ultrasound examination to estimate fetal size for 340 of the women participating in FLAG part A. These women will have an ultrasound performed at 28 weeks and 36 weeks gestation around the same time as their research blood sample is collected.

We are collecting detailed information on each of the women involved in the study, including birth outcomes and the health of the baby. We are using a range of sophisticated techniques to characterise the well-grown from the ‘starved’ newborn, including body fat composition analysis with the state-of-the-art PEA POD machine.

If slowing of fetal growth in late pregnancy is found to be an important indicator of placental insufficiency, we may uncover a previously unrecognised cohort at risk of late pregnancy stillbirth that would benefit from planned timing of birth.

Where is the FLAG study up to now?

The FLAG study started recruiting pregnant women booked at the Mercy Hospital for Women in early 2015. As of late 2016, we have already reached our target sample size of 2000 participants for Part A and 340 women for Part B. This amazing progress is due to the incredible dedication of our research team and the huge support from our pregnant women. We are excited to announce that the crucial laboratory analysis is currently underway in the laboratories of Mercy Perinatal and the Australian Genome Research Facility and we plan to share our research findings throughout 2017 and 2018.

The FLAG team

Chief investigators

Professor Sue Walker
Professor Stephen Tong
Clare Whitehead
A/Prof Lisa Hui

PhD student

Dr Teresa MacDonald

Associate investigators

Dr Alice Robinson

Research midwives

Kirsten Dane
Anna Middleton
Val Kyritsis
Gabrielle Pell

Research assistants

Sally Beard
Ping Cannon
Roxanne Hastie
Elizabeth Lockie

Bioinformatics consultant

Lavinia Gordon

Who helped us make this happen?

We are very grateful to our many supporters, including:
National Health and Medical Research Council (Project grant ID 1065854)
Mercy Health Foundation
Stillbirth Foundation
Norman Beischer Medical Research Foundation
University of Melbourne
Mercy Health Academic Research and Development Committee
Harold Mitchell Travel Fellowship
RANZCOG Research Foundation