title: Higher urinary bisphenol A concentration is associated with unexplained recurrent miscarriage risk: evidence from a case-control study in eastern China.
abstract: BACKGROUND
  Evidence about the association between Bisphenol A (BPA) and the risk of recurrent miscarriage (RM) in human being is still limited.
  
  
  OBJECTIVE
  We evaluated the association of urinary BPA concentrations with RM in human being.
  
  
  METHODS
  A hospital-based 1:2 matched case-control study on RM was carried out in Suzhou and Kunshan in Jiangsu Province in China between August 2008 and November 2011. Total urinary BPA concentrations in 264 eligible urine samples (102 RM patients and 162 controls) were measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The Wilcoxon test and conditional logistic regression were used to estimate the differences between the groups and odds ratios (OR) with 95% confidence intervals (CI), respectively.
  
  
  RESULTS
  The median ± IQR (interquartile range) (P75-P25) values of non-creatinine-adjusted total urinary BPA levels in the RM patients and the controls were 1.66 ± 3.69 ng/ml and 0.58 ± 1.07 ng/ml, respectively (0.98 ± 2.67 μg/g Cr (creatinine) and 0.40 ± 0.77 μg/g Cr. The adjusted BPA level was significantly higher in the RM patients than in the controls (Wilcoxon test, Z = 4.476, P < 0.001). Higher level of urinary BPA was significantly associated with an increased risk of RM (P-trend < 0.001). Compared to the groups with urinary BPA levels less than 0.16 μg/g Cr, the women with levels of 0.40-0.93 μg/g Cr and 0.93 μg/g Cr or above had a significantly higher risk of RM (OR = 3.91, 95%CI: 1.23-12.45 and OR = 9.34, 95%CI: 3.06-28.44) that persisted after adjusting for confounding factors. The time from recently RM date to recruitment does not significantly influence the urinary BPA level (P = 0.090).
  
  
  CONCLUSIONS
  Exposure to BPA may be associated with RM risk.
authors.affiliation: Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Department of Epidemiology and Health Statistics School of Public Health, Soochow University, Suzhou, 215123, PR China.
authors.forename: Yueping
authors.initials: Y
authors.lastname: Shen
authors.affiliation: Suzhou Center for Disease Prevention and Control, Suzhou 215004, China.
authors.forename: Yanmin
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: The Third Affiliated Hospital, Suzhou University, Changzhou 213003, China.
authors.forename: Jingting
authors.initials: J
authors.lastname: Jiang
authors.affiliation: Department of Nosocomial Infection and Disease Control, Shanghai Tenth People's Hospital, Shanghai 200072, China.
authors.forename: Yinmei
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Maternal and Child Health Bureau of Kunshan, Kunshan 215301, China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Luo
authors.affiliation: Department of Obstetrics and Gynaecology, First Affiliated Hospital of Soochow University, Suzhou 215006, China.
authors.forename: Zongji
authors.initials: Z
authors.lastname: Shen
authors.affiliation: Department of Obstetrics and Gynaecology, Second Affiliated Hospital of Soochow University, Suzhou 215004, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Chen
authors.affiliation: School of Radiation Medicine and Protection, Medical College of Soochow University, Suzhou 215123, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Radiation Medicine and Protection, Medical College of Soochow University, Suzhou 215123, China.
authors.forename: Yiheng
authors.initials: Y
authors.lastname: Dai
authors.affiliation: School of Radiation Medicine and Protection, Medical College of Soochow University, Suzhou 215123, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Department of Reproductive Epidemiology and Social Science, Shanghai Institute of Planned Parenthood Research, Shanghai 200032, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Liang
authors.affiliation: Division of Epidemiology and Biostatistics, Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, Ohio 45221, United States of America.
authors.forename: Aimin
authors.initials: A
authors.lastname: Chen
authors.affiliation: Department of Reproductive Epidemiology and Social Science, Shanghai Institute of Planned Parenthood Research, Shanghai 200032, China; NPFPC Laboratory of Contraception and Devices, Shanghai 200032, China; Institute of Reproduction & Development, Fudan University, Shanghai 200032, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Yuan
mesh_terms: D000026:Abortion, Habitual / Q000652:urine*; D000328:Adult; D001559:Benzhydryl Compounds / Q000652:urine*; D016022:Case-Control Studies; D002681:China; D003404:Creatinine / Q000652:urine; D003710:Demography; D005260:Female; D006801:Humans; D010636:Phenols / Q000652:urine*; D012015:Reference Standards; D012307:Risk Factors; D013997:Time Factors; D055815:Young Adult; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D003404:Creatinine; D010636:Phenols; C006780:bisphenol A; D000098826:Bisphenol A Compounds