title: Urinary bisphenol A concentrations and early reproductive health outcomes among women undergoing IVF.
abstract: OBJECTIVE
  In women undergoing IVF, are urinary bisphenol A (BPA) concentrations associated with ovarian response and early reproductive outcomes, including oocyte maturation and fertilization, Day 3 embryo quality and blastocyst formation?
  
  
  CONCLUSIONS
  Higher urinary BPA concentrations were found to be associated with decreased ovarian response, number of fertilized oocytes and decreased blastocyst formation.
  
  
  BACKGROUND
  Experimental animal and in vitro studies have reported associations between BPA exposure and adverse reproductive outcomes. We previously reported an association between urinary BPA and decreased ovarian response [peak serum estradiol (E(2)) and oocyte count at the time of retrieval] in women undergoing IVF; however, there are limited human data on reproductive health outcomes, such as fertilization and embryo development.
  
  
  METHODS
  Prospective preconception cohort study. One hundred and seventy-four women aged 18-45 years and undergoing 237 IVF cycles were recruited at the Massachusetts General Hospital Fertility Center, Boston, MA, USA, between November 2004 and August 2010. These women were followed until they either had a live birth or discontinued treatment. Cryothaw and donor egg cycles were not included in the analysis.
  
  
  METHODS
  Urinary BPA concentrations were measured by online solid-phase extraction-high-performance liquid chromatography-isotope dilution-tandem mass spectrometry. Mixed effect models, poisson regression and multivariate logistic regression models were used wherever appropriate to evaluate the association between cycle-specific urinary BPA concentrations and measures of ovarian response, oocyte maturation (metaphase II), fertilization, embryo quality and cleavage rate. We accounted for correlation among multiple IVF cycles in the same woman using generalized estimating equations.
  
  
  RESULTS
  The geometric mean (SD) for urinary BPA concentrations was 1.50 (2.22) µg/l. After adjustment for age and other potential confounders (Day 3 serum FSH, smoking, BMI), there was a significant linear dose-response association between increased urinary BPA concentrations and decreased number of oocytes (overall and mature), decreased number of normally fertilized oocytes and decreased E(2) levels (mean decreases of 40, 253 and 471 pg/ml for urinary BPA quartiles 2, 3 and 4, when compared with the lowest quartile, respectively; P-value for trend = 0.001). The mean number of oocytes and normally fertilized oocytes decreased by 24 and 27%, respectively, for the highest versus the lowest quartile of urinary BPA (trend test P < 0.001 and 0.002, respectively). Women with urinary BPA above the lowest quartile had decreased blastocyst formation (trend test P-value = 0.08).
  
  
  CONCLUSIONS
  Potential limitations include exposure misclassification due to the very short half-life of BPA and its high variability over time; uncertainty about the generalizability of the results to the general population of women conceiving naturally and limited sample.
  
  
  CONCLUSIONS
  The results from this extended study, using IVF as a model to study early reproductive health outcomes in humans, indicate a negative dose-response association between urinary BPA concentrations and serum peak E(2) and oocyte yield, confirming our previous findings. In addition, we found significantly decreased metaphase II oocyte count and number of normally fertilizing oocytes and a suggestive association between BPA urinary concentrations and decreased blastocyst formation, thus indicating that BPA may alter reproductive function in susceptible women undergoing IVF.
  
  
  BACKGROUND
  This work was supported by grants ES009718 and ES000002 from the National Institute of Environmental Health Sciences and grant OH008578 from the National Institute for Occupational Safety and Health. None of the authors has actual or potential competing financial interests.
  
  
  CONCLUSIONS
  The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention.
authors.affiliation: Department of Environmental Health,  Harvard School of Public Health, 665 Huntington Avenue, Building I, 14th Floor, Boston, MA 02115,  USA.
authors.forename: Shelley
authors.initials: S
authors.lastname: Ehrlich
authors.forename: Paige L
authors.initials: PL
authors.lastname: Williams
authors.forename: Stacey A
authors.initials: SA
authors.lastname: Missmer
authors.forename: Jodi A
authors.initials: JA
authors.lastname: Flaws
authors.forename: Xiaoyun
authors.initials: X
authors.lastname: Ye
authors.forename: Antonia M
authors.initials: AM
authors.lastname: Calafat
authors.forename: John C
authors.initials: JC
authors.lastname: Petrozza
authors.forename: Diane
authors.initials: D
authors.lastname: Wright
authors.forename: Russ
authors.initials: R
authors.lastname: Hauser
mesh_terms: D000293:Adolescent; D000328:Adult; D001559:Benzhydryl Compounds / Q000652:urine*; D015331:Cohort Studies; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D008404:Massachusetts; D008875:Middle Aged; D009865:Oocytes / Q000187:drug effects*; D010062:Ovulation Induction / Q000379:methods; D010636:Phenols / Q000652:urine*; D011247:Pregnancy; D018873:Pregnancy Rate; D011446:Prospective Studies; D060728:Reproductive Health; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D010636:Phenols; C006780:bisphenol A; D000098826:Bisphenol A Compounds