Forty Years of Assessing Neurodevelopmental and Behavioral Effects of Prenatal Alcohol Exposure in Infants: What Have We Learned?

Abstract

It has been known for over 4 decades that prenatal alcohol exposure (PAE) can adversely affect neurodevelopment and behavior (NDB). Yet, early detection of altered NDB due to PAE continues to present a major clinical challenge. Identification of altered NDB in the first 2years of life, before higher-order cognitive processes develop, invites early interventions for affected children to improve long-term outcomes. Studies published in English from January of 1980 to July of 2018 were identified in PubMed/MEDLINE. The review focused on prospective birth cohort studies which used standardized NDB assessments in children up to 2years of age, wherein PAE was the main exposure and NDB was the main outcome. NDB was categorized into the domains of neurocognitive, adaptive, and self-regulation based on the 2016 Updated Clinical Guidelines for Diagnosing fetal alcohol spectrum disorder. An initial search resulted in 1,867 articles for which we reviewed abstracts; 114 were selected for full-text review; and 3 additional abstracts were identified through review of references in eligible publications. Thirty-one publications met criteria and were included: of these, 24 reported neurocognitive outcomes, 24 reported adaptive behavior outcomes, and 12 reported outcomes in the domain of self-regulation. Although self-regulation was assessed in the fewest number of studies, 8/12 (75%) reported PAE-associated deficits. In contrast, results were mixed for the other 2 domains: 13/24 (54%) of the selected studies that included neurocognitive outcomes showed poorer performance following PAE, and 8/24 (33%) studies that assessed adaptive functioning found significant differences between PAE and comparison infants. There is considerable evidence to support the value of early-life assessments of infant NDB when PAE is known or suspected. More studies focusing on infant self-regulation, in particular, are needed to determine the utility of early evaluation of this critical developmental domain in infants with PAE.