Cerebral redistribution in late-onset fetal growth restriction: not always the same story (Winner of the SIMP EUBRAIN Award, in memory of J. Claudine Larroche for the study on PVL in 1962)

Objective. To evaluate perinatal outcomes of late-onset FGR fetuses showing cerebral redistribution in relation to modifications of Doppler components of cerebroplacental ratio (CPR).
Materials and Methods. Multicentre retrospective study including non-anomalous singleton pregnancies complicated by late-onset FGR featuring CPR < 5° P. Perinatal outcomes were compared across four subgroups:

1. fetuses showing UAPI < 95° P and MCAPI > 5° P;
2. UAPI > 95° P and MCAPI > 5° P;
3. UAPI < 95° P and MCAPI < 5° P;
4. UAPI > 95° P and MCAPI < 5 °P.

Results. 308 cases were included: 33.4% belonged to group 1, 28.8% group 2, 20.5% group 3, 17.2% group 4. Group 2 was associated with lower gestational age at delivery (37+0+2+1 vs 38+0+1+6, 37+5+1+6 and 37+5+1+6 weeks for groups 1, 3 and 4 respectively, p = 0.01) and birthweight (2178+509 vs 2451+470, 2362+496 and 2416+450 g for groups 1, 3 and 4 respectively, p < 0.01), higher incidence of cesarean delivery (49.4% vs 26.5%, 37.1% and 34.0% for groups 1, 3 and 4 respectively, p = 0.04), delivery < 37 weeks (47.2% vs 20.4%, 25.4% and 30.2%, for groups 1, 3 and 4 respectively, p < 0.01), need for respiratory support at birth (22.5% vs 7.8%, 7.9% and 9.4% for groups 1, 3 and 4 respectively, p < 0.01), NICU admission (42.7% vs 20.4%, 20.6% and 34.0% for groups 1, 3 and 4 respectively, p < 0.01), composite adverse outcome (38.2% vs 16.5%, 15.9% and 24.5% for groups 1, 3 and 4 respectively, p < 0.01) and longer neonatal hospital admission (8 vs 4, 5 and 6) for groups 1, 3 and 4, respectively, p < 0.01).
Conclusions. The worst perinatal outcomes in late-onset FGR with cerebral redistribution occur when characterized by increased UAPI but normal MCAPI.