Antenatal Melatonin Supplementation for Neuroprotection in Fetal Growth Restriction

Fetal growth restriction (FGR) is a significant health care issue, affecting 20,000 Australian pregnancies every year. Undetected FGR is one of the key risk factors for stillbirth, but FGR can also cause significant impairments in short and long-term health outcomes for the child.It is a major risk factor for preterm birth and is a recognised causal pathway to the neurodevelopmental injury underlying cognitive and behavioural impairment and cerebral palsy. Current obstetric care is focused on the detection of the growth restricted fetus and then ultrasound assessment of fetal wellbeing to guide timing of delivery. This approach seeks to maximize the gestational age of the fetus at delivery to minimise the risks of prematurity, while delivering the fetus in time to reduce the likelihood of stillbirth. Currently, no therapies exist that can maximize fetal wellbeing in the setting of growth restriction and minimise the frequency of antenatally acquired brain injury due to in-utero hypoxia.This triple-blind, randomized, parallel group, placebo-controlled trial will administer maternal melatonin or placebo supplementation antenatally in the setting of early-onset severe FGR to determine whether melatonin can PROTECT the fetal brain and lead to improved neurodevelopmental outcomes.

Inclusion Criteria:Singleton PregnancySevere fetal growth restriction, defined as:Abdominal circumference ≤3rd centile for gestational age according to charts supplied that have been adapted from Westerway et al; orAbdominal circumference <10th centile in combination with at least one abnormal fetoplacental Doppler study, being:Uterine artery (raised pulsatility index ≥95th centile)Umbilical artery (pulsatility index ≥95th centile or absent/reversed end-diastolic flow)Confirmed 23+0 - 31+6 weeks' gestationAge ≥18 yearsUnderstand EnglishExclusion Criteria:A fetus with a known chromosomal, major structural anomaly or non-placental cause of fetal growth restrictionPregnancies requiring immediate delivery (e.g. absent A wave in ductus venosus, preterminal CTG or biophysical profile)Co-recruitment in another clinical trial where a pharmaceutical product or nutritional supplement impacting on oxidative stress is the trial intervention.Currently prescribed Fluvoxamine