Modeling Prenatal Adversity/Advantage: Effects on Birth Weight
Importance: How maternal experiences of adversity/advantage during pregnancy impact the developing fetus remains unclear. Objective: Using prospective data about experiences of adversity/advantage and other factors known to impact fetal developmental, we explored how these risk and protective factors relate to each other and impact infant birth weight by gestational age. Design: A prospective study that collected data on of forms of social advantage/disadvantage, and psychological factors from pregnant women during each trimester of pregnancy that accounted for maternal medical and nutritional status. We aimed to determine the differential impact of social advantage/disadvantage and adversity and psychological factors on infant birthweight accounting for gestational age. Structural Equation Modeling (SEM) was used to investigate the relationship of these forms of adversity as latent constructs on infant outcome. The follow-up of children is ongoing as a part of the Early Life Adversity Biological Embedding and Risk for Developmental Precursors of Mental Disorders (eLABE). Data collection was conducted from 2017-2020. Setting: An academic medical center. Participants: Pregnant women who were participants in a study of preterm birth within the Prematurity Research Center at Washington University in St. Louis with negative drug screens (other than cannabis) and without known pregnancy complications or known fetal congenital problems, were invited for participation. N=395 mothers were included in the analysis and N=268 eligible subjects declined participation. N=399 singleton offspring were included. Main Outcome(s) and Measure(s): Birthweight accounting for gestational age. Results: The study included N=395 pregnant women and their N=399 singleton offspring. The Social Advantage latent factor significantly predicted the residual birthweight after accounting for gestational age (p=.006) representing a 2.57% increase in residual gestational age-adjusted birthweight for each one standard deviation increase in the Social Advantage. The only other significant predictor was pre-pregnancy BMI (p=.019) which was associated with increased birthweight by gestational age while the Psychosocial Stress factor was no longer significant when other factors were accounted for. Conclusions and Relevance: Findings elucidate the significant effects of social adversity on the developing fetus and underscore the need to protect pregnant women in this risk group.