Polybrominated diphenyl ethers (PBDEs) are widely used in commercial and household products. Few human studies have examined the effects of PBDE exposure on female reproductive function. We recruited 207 pregnant women when they were admitted for labor from September 2010 to February 2012 as part of a birth cohort study, the Laizhou Wan Birth Cohort study. Maternal sera were analyzed for eight PBDE congeners (BDE28, -47, -85, -99, -100, -153, -154, and -183) and four sex hormones. BDE-153 exhibited the highest serumlevel (median 4.67 ng/g lipid), followed by BDE-99 (median 3.45 ng/g lipid) and BDE-28, -47, and -100 (medians near 2 ng/g lipid). BDE-28, -47, -99, -100, and -153 were the most frequently detected (N90%) congeners. Follicle-stimulating hormone (FSH) levels were negatively associated with PBDE exposure. For each natural log unit increase in BDE47, 100, andS5PBDEs, FSH levels changed -1.19 IU/L (95% confidence interval [CI]: -1.32, -1.02), -1.17 IU/L (95% CI:-1.36,-1.01) and-1.26 IU/L (95% CI:-1.55,-1.02) respectively. BDE-85,-153, and-183 were associated with adverse reproductive effects, including an increased risk of threatened abortion (odds ratio [OR] [95% CI]: 1.30 [1.03, 1.62], 1.04 [1.01, 1.08], and 1.03 [1.01, 1.06], respectively). BDE-153 was associated with an increased risk of premature birth (adjusted OR [95% CI]: 1.05 [1.01, 1.09]), and BDE-28 was associated with longer time to pregnancy (adjusted OR [95% CI]: 1.34 [1.03, 1.76]). These findings suggest that maternal PBDE exposure may be inversely associated with female reproductive function. (C) 2016 Published by Elsevier B.V.