The developmental risk linked to mild-to-moderate prenatal alcohol exposure (PAE) can be identified in infants, according to a study that tested a screening tool with 130 newborns. In alcohol-exposed babies, the tool picked up subtle differences in attention and regulation that are associated with lower cognitive and motor functioning in early childhood.

This finding points to a critical opportunity for early intervention and the potential for improving long-term outcomes. People exposed to alcohol in utero can face lifelong impacts on their physical growth, learning, and behavior, a constellation of symptoms known as Fetal Alcohol Spectrum Disorder (FASD). In the US, up to 1 in 20 school-age children may be affected by FASD. FASD is typically not identified until children are in school, and misdiagnoses are common.

The effects of mild-to-moderate PAE, the most common range of exposure, have been especially challenging to characterise. For the study in Alcohol: Clinical & Experimental Research, investigators tested a tool assessing newborns’ neurological and behavioral responses that had not previously been studied with infants exposed to alcohol in utero.

Researchers aimed to determine whether the Neonatal Intensive Care Unit Network Neurobehavioral Scale, First Edition (NNNS-I) could distinguish between infants with low-to-moderate PAE and those without PAE. They worked with parents who were pregnant between 2018 and 2022 and evaluated 130 babies from birth to age 6–9 months.

Babies of parents with self-reported alcohol use during pregnancy or positive biomarkers for alcohol were assigned to a PAE group (55%); the others (45%) made up the control group. The babies’ neurodevelopment was assessed soon after birth and again at 6­­–9 months. The tracked behaviors in the newborn period included alertness, self-soothing, excitability, lethargy, muscle tone, reflexes, and others.

The researchers used statistical analysis to look for associations between the babies’ neurodevelopmental measures and PAE. Based on NNNS-I scores, the babies were assigned a profile indicating behavioral risk (high, mixed, or low).

The average reported alcohol consumption of parents in the PAE group was 1.1 drinks a week; 2 in 3 reported at least one episode of binge drinking, with the majority of those occurring in the periconceptional period, and 3 in 5 had at least one positive biomarker for alcohol. On the NNNS-I, infants with PAE scored higher than the no-exposure babies for lethargy, hypertonicity (higher muscle tone), lower attention scores, and stress signs during the testing (such as tremors ), an unusual combination.

After adjusting for certain other factors, the attention and lethargy scores remained significant. Based on their scores, 28 babies were considered at high behavioral risk, 22 at mixed behavioral risk, and 53 at low behavioral risk. All 3 profiles included infants with PAE, reflecting the variability of outcomes. Nevertheless, the study revealed significant differences in NNNS-I scores among babies with mild-to-moderate PAE and no PAE, and infants with positive biomarkers for alcohol were more likely to be in the high-risk group.

While the NNNS-I is not a diagnostic tool, it identified shortly after birth a distinct neurobehavioral profile associated with mild-to-moderate PAE and brain vulnerabilities implicated in FASD. The findings point to the possibility of providing more intensive follow-up and monitoring and neurodevelopmental intervention much earlier in life. Studies that track children’s development over time are needed to show whether the NNNS-I can predict FASD.