Prenatal Exposure to Early Life Adversity and Neonatal Brain Volumes at Birth
Authors: Triplett Regina L. , Lean Rachel E. , Parikh Amisha , Miller J. Philip , Alexopoulos Dimitrios , Kaplan Sydney , Meyer Dominique , Adamson Chris , Smyser Tara A. , Rogers Cynthia E. , Barch Deanna M. , Warner Barbara , Luby Joan L. , Smyser Christopher D. 
Published: December 2021

Importance

Exposure to early life adversity alters the structural development of key brain regions underlying neurodevelopmental impairments. The extent that prenatal exposure to life adversity alters structure at birth remains poorly understood.

Objective

To determine if prenatal exposure to maternal social advantage and psychosocial distress alters global and regional brain volumes and cortical folding in the first weeks of life.

Design

A prospective, longitudinal study of sociodemographically-diverse mothers recruited in the first trimester of pregnancy and their infants who underwent brain magnetic resonance imaging scan in the first weeks of life.

Setting

Mothers were recruited from local obstetric clinics from 2017-2020.

Participants

Of 399 mother-infant dyads prospectively recruited into the parent study, 280 healthy, term-born infants (47% female, mean postmenstrual age at scan 42 weeks) were eligible for inclusion.

Exposures

Maternal social advantage and psychosocial distress in pregnancy.

Main Measures and Outcomes

Two measures of latent constructs were created using Confirmatory Factor Analyses spanning Maternal Social Advantage (Income to Needs ratio, Area Deprivation Index, Healthy Eating Index, education level, insurance status) and Psychosocial Stress (Perceived Stress Scale, Edinburgh Postnatal Depression Scale, Everyday Discrimination Scale, Stress and Adversity Inventory). Neonatal cortical and subcortical gray matter, white matter, cerebellar, hippocampus, and amygdala volumes were generated using semi-automated age-specific segmentation pipelines.

Results

After covariate adjustment and multiple comparisons correction, greater social disadvantage (i.e., lower Advantage values) was associated with reduced cortical gray matter (p=.03), subcortical gray matter (p=.008), and white matter (p=.004) volumes and cortical folding (p=.001). Psychosocial Stress was not related to neonatal brain metrics. While social disadvantage was associated with smaller absolute volumes of the bilateral hippocampi and amygdalae, after correcting for total brain volume, there were no regional effects.

Conclusions and Relevance

Prenatal exposure to social disadvantage is associated with global reductions in brain volumes and cortical folding at birth. No regional specificity for the hippocampus or amygdala was detected. Results highlight that the deleterious effects of poverty beginin uteroand are evident in the first weeks of life. These findings emphasize that preventative interventions to support fetal brain development should address socioeconomic hardships for expectant parents.

KEY POINTS

Question

Does prenatal exposure to maternal social disadvantage and psychosocial distress alter global and relative brain volumes at birth?

Findings

In this longitudinal, observational study of 280 mother-infant dyads, prenatal exposure to greater maternal social disadvantage, but not psychosocial distress, was associated with reduced white matter, cortical gray matter, and subcortical gray matter volumes and cortical folding at birth after accounting for maternal health and diet. There were no differential effects in the hippocampus or amygdala.

Meaning

Prenatal exposure to social disadvantage is associated with global reductions in brain volumes and folding in the first weeks of life.