Background: Prior studies suggest associations between fetal exposure to antimicrobial and paraben compounds with adverse reproductive outcomes, mainly in animal models. We have previously reported elevated levels of these compounds for a cohort of mothers and neonates. Objective: We examined the relationship between human exposure to parabens and antimicrobial compounds and birth outcomes including birth weight, body length and head size, and gestational age at birth. Methods: Maternal third trimester urinary and umbilical cord blood plasma concentrations of methylparaben (MePB), ethylparaben (EtPB), propylparaben (PrPB), butylparaben (BuPB), benzylparaben (BePB), triclosan (2,4,4'-trichloro-2'-hydroxydiphenyl ether or TCS) and triclocarban (1-(4-chlorophenyl)-3-(3,4dichlorophenyl) urea or TCC), were measured in 185 mothers and 34 paired singleton neonates in New York, 2007-2009. Results: In regression models adjusting for confounders, adverse exposure-outcome associations observed included increased odds of PTB (BuPB), decreased gestational age at birth (BuPB and TCC) and birth weight (BuPB), decreased body length (PrPB) and protective effects on PTB (BePB) and LBW (3'-C1-TCC) (p < 0.05). No associations were observed for MePB, EtPB, or TCS. Conclusions: This study provides the first evidence of associations between antimicrobials and potential adverse birth outcomes in neonates. Findings are consistent with animal data suggesting endocrine disrupting potential resulting in developmental and reproductive toxicity. (C) 2016 Elsevier B.V. All rights reserved.