Fetal growth restriction alters brain structure in the womb

For the first time Hudson Institute researchers have shown how fetal growth restriction (FGR), a condition may impact brain development, and affects up to one in 10 babies, gradually worsens during pregnancy.

FGR can lead to a number of damaging outcomes including stillbirth in utero, behavioural and cognitive damage, and cerebral palsy after birth. During an affected pregnancy, FGR alters the part of the brain that controls motor function, called the cerebellum.

The new findings published in Frontiers of Physiology, confirm that brain injuries develop in the womb and, as a result, treatments to improve outcomes for babies with FGR should begin as soon as possible, preferably before birth or soon after birth.

Associate Professor Suzanne Miller, Dr Tamara Yawno and colleagues (Hudson Institute and Department of Obstetrics and Gynaecology, Monash University) looked at the structure of the cerebellum at three points in time during pregnancy and compared normal and abnormal development.

The study demonstrates that as FGR advances during pregnancy, the changes to the structure of the cerebellum become more obvious. The results suggest that the longer the pregnancy goes on, the greater the risk to the unborn child.

What is fetal growth restriction?

FGR is a condition where the baby stops growing in the womb and is born very small.

The most common cause of FGR is the placenta failing to deliver the amount of oxygen and nutrients required to meet the baby’s needs. Reduced oxygen supply results in oxidative stress, causing injury to the baby’s developing brain in the weeks prior to birth.

Another piece of the jigsaw

This knowledge provides another piece in the jigsaw to assist in a world-first clinical trial at Monash Medical Centre. The trial, led by Dr Kirsten Palmer, examines melatonin therapy to protect the developing brain in pregnancies affected by FGR.

RISK FACTORS FOR FETAL GROWTH RESTRICTION

Maternal factors | High blood pressure, smoking, alcohol or drug intake, malnutrition or disease (kidney/diabetes/heart/respiratory/infection).

Uterine/placental factors | Decreased blood flow in the uterus and placenta, detachment of the placenta from the uterus, the placenta attaching too low in the uterus, or infection in tissues around the fetus.

Fetus-related factors | Multiple gestation, infection, birth defects, chromosomal abnormality.