Prenatal risk factors for internalizing and externalizing problems in childhood

Background: A growing body of research has documented the effects of prenatal risk factors on a wide spectrum of adverse offspring health outcomes. Childhood behavior problems, such as externalizing and internalizing problems, are no exception. This comprehensive literature review aims to summarize and synthesize current research about commonly experienced prenatal risk factors associated with internalizing and externalizing problems, with a focus on their impact during childhood and adolescence. Potential mechanisms as well as implications are also outlined. Data sources: The EBSCO, Web of Science, PubMed, Google Scholar, and Scopus databases were searched for studies examining the association between prenatal risk factors and offspring internalizing/externalizing problems, using keywords “prenatal” or “perinatal” or “birth complications” in combination with “internalizing” or “externalizing”. Relevant articles, including experimental research, systematic reviews, meta-analyses, cross-sectional and longitudinal cohort studies, and theoretical literature, were reviewed and synthesized to form the basis of this integrative review. Results: Prenatal risk factors that have been widely investigated with regards to offspring internalizing and externalizing problems encompass health-related risk factors, including maternal overweight/obesity, substance use/abuse, environmental toxicant exposure, maternal infection/inflammation, as well as psychosocial risk factors, including intimate partner violence, and anxiety/depression. Collectively, both epidemiological and experimental studies support the adverse associations between these prenatal factors and increased risk of emotional/behavioral problem development during childhood and beyond. Potential mechanisms of action underlying these associations include hormonal and immune system alterations. Implications include prenatal education, screening, and intervention strategies. Conclusions: Prenatal risk factors are associated with a constellation of offspring internalizing and externalizing problems. Identifying these risk factors and understanding potential mechanisms will help to develop effective, evidence-based prevention, and intervention strategies.