Objective: To assess the potential effect of bisphenol A (BPA), triclosan (TCS), and phthalates on women's fecundity, as measured by time to pregnancy (TTP). Design: Pregnancy-based retrospective TTP study. Setting: Not applicable. Patient(s): A total of 2,001 women during the first trimester of pregnancy recruited between 2008 and 2011 (the Maternal-Infant Research on Environmental Chemicals (MIREC) Study), with 1,742 women included in the BPA analysis, 1,699 in the TCS analysis, and 1,597 in

more »

... he phthalates analysis. Intervention(s): None. Main Outcome Measure(s): Fecundability odds ratios (FORs) estimated using the Cox model modified for discrete time data. Result(s): The BPA concentrations were not statistically significantly associated with diminished fecundity either in crude or adjusted models. Women in the highest quartile of TCS (>72 ng/mL) had evidence of decreased fecundity (FOR 0.84; 95% confidence interval, 0.72-0.97) compared with the three lower quartiles as the reference group. Exposure to phthalates was suggestive of a shorter TTP, as indicated by FORs greater than 1, although the 95% confidence interval always included 1. Conclusion(s): Elevated TCS exposure may be associated with diminished fecundity. BPA and phthalates showed no negative impact; on the contrary, some phthalates might be associated with a shorter time to pregnancy. A major limitation of the study was that only one measurement of exposure was available for each woman after conception. Further research is necessary to test these findings.