Prenatal exposure to multiple metals and birth outcomes: An observational study within the National Children's Study cohort

•Prenatal exposure to metals may play an important role in fetal growth.•Lead was inversely related to birthweight, birth length, head circumference, and gestational age among female infants.•Selenium was positively associated with ponderal index and inversely associated with birth length among female infants.•Selenium was positively related to birthweight among male infants.•Infant sex may modify associations between prenatal metal exposures and birth outcomes.