Background: There is no consensus in the literature as to whether maternal zinc nutriture is associated with pregnancy outcome or fetal growth. Objective: We evaluated the associations between plasma zinc concentrations during pregnancy and various measures of pregnancy outcome and neonatal conditions at birth. Design: We measured zinc concentrations in plasma samples obtained at a mean of 16 wk of gestation (range: 6-34 wk) from 3448 women who were screened for a trial designed to evaluate the effect of zinc supplementation on fetal growth. Subjects were from low socioeconomic backgrounds and attended a public health clinic for their prenatal care. Plasma zinc concentrations were compared with pregnancy outcome, including complications during pregnancy and delivery, and anthropometric measures and Apgar scores of neonates. Results: Plasma zinc concentrations declined as gestation progressed. After plasma zinc concentrations were adjusted for gestational age, they were not significantly associated with any measure of pregnancy outcome or neonatal condition. Conclusion: We conclude that plasma zinc concentrations during the late first trimester to the early third trimester do not predict pregnancy outcomes in women of a low socioeconomic background.