Fetal growth restriction is associated with pregnancy complications, as well as high rates of preterm birth and childhood disabilities. This is a complex disorder that impacts the development of the placenta and limits blood flow to the fetal brain, depriving the fetus of oxygen and nutrients needed to grow. What’s more, is that fetal growth restriction is very common and impacts 6 in 100 pregnancies in Canada. In the developing world, fetal growth restriction is more common and worldwide fetal growth restriction impacts ~30 million pregnancies per year. Presently, there are no treatments or therapies available. Early delivery is medically advised for pregnant women experiencing growth restriction; however preterm delivery comes at a high cost as babies born early are at high risk for infection and brain injury due to their immaturity that place them at risk for developmental disabilities. Better tools are needed to diagnose and monitor pregnant women whose fetuses are at risk for growth restriction.
Presently, fetal growth restriction is diagnosed and monitored using Doppler ultrasound. Using this technique, blood flow to the placenta and fetal brain are assessed. However, Doppler ultrasound may only be able to detect more advanced stages of fetal growth restrictions, when decreases in blood flow are severe. Advances in magnetic resonance imaging (MRI) now allow for the imaging of placental blood flow and the fetal brain at the same time. For the current proposal, we will assess whether MRI-based measures of placental function are better predictors of fetal brain health and delivery times compared to Doppler ultrasound in growth-restricted fetuses.
Developing sensitive MRI-biomarkers for placental function predictive of fetal development in growth restricted fetuses who are at risk for preterm birth can better inform delivery times. Sensitive biomarkers can also be used to test the efficacy of antenatal interventions for growth restriction.