Prenatal Exposure to Manganese and Maternal Psychosocial Stress-Suppression during Pregnancy Jointly Contributes to Restricted Fetal Growth

摘要

Introduction Metals exposure and psychosocial stress during pregnancy can contribute to poor birth outcomes. Recent work has shown early life exposure to metals and psychosocial factors jointly contribute to child growth and development. It is unknown whether prenatal metals and psychosocial stress would similarly interact and jointly affect birth outcomes. This study fills this gap and tests whether manganese exposure and maternal stress-suppression during pregnancy would synergistically affect infant birth outcomes. Methods Data were collected from the Albany Infant and Mother Study, an ongoing birth cohort. Manganese exposure was assessed in 150 subjects via toenail sample collected late in pregnancy. Maternal stress-suppression was assessed via a gold-standard questionnaire during pregnancy. Birthweight, head circumference, and infant cephalization indices ((head circumference/birthweight)*100) were gathered from medical records and examined as outcomes. Multivariate regression models tested main effects and interaction between suppression and manganese in relation to infant birth size outcomes, adjusting for demographic, maternal health, delivery, and infant factors. Results A significant interaction between manganese and stress-suppression was observed in relation to infant cephalization (6=0.02, SE=0.01, p<0.05), indicating that infants whose mothers had high levels of manganese and high levels of suppression experienced more asymmetric fetal growth than other groups. Interaction effects were not observed for birthweight or head circumference. Discussion the combined effect of stress-suppression and high manganese exposure during pregnancy contributed to asymmetric intrauterine growth restriction among offspring, indicating potential brain sparing during fetal development. This synergistic effect exceeds that of the main effects of each factor. Interventions designed to promote healthy birth outcomes should consider both metals and psychosocial factors.