Urinary Concentrations of Parabens and Other Antimicrobial Chemicals and Their Association with Couples' Fecundity

BACKGROUND: Human exposure to parabens and other antimicrobial chemicals is continual and pervasive. The hormone-disrupting properties of these environmental chemicals may adversely affect human reproduction. OBJECTIVE: We aimed to prospectively assess couples' urinary concentrations of antimicrobial chemicals in the context of fecundity, measured as time to pregnancy (TTP). METHODS: In a prospective cohort of 501 couples, we examined preconception urinary chemical concentrations of parabens, triclosan and triclorcarban in relation to TTP; chemical concentrations were modeled both continuously and in quartiles. Cox's proportional odds models for discrete survival time were used to estimate fecundability odds ratios (FORs) and 95% confidence intervals (CIs) adjusting for apriori-defined confounders. In light of TTP being a couple-dependent outcome, both partner and couple-based exposure models were analyzed. In all models, FOR -estimates < 1.0 denote diminished fecundity (longer TTP). RESULTS: Overall, 347 (69%) couples became pregnant. The highest quartile of female urinary methyl paraben (MP) concentrations relative to the lowest reflected a 34% reduction in fecundity (aFOR= 0.66; 95% CI: 0.45, 0.97) and remained so when accounting for couples' concentrations (aFOR= 0.63; 95% CI: 0.41, 0.96). Similar associations were observed between ethyl paraben (EP) and couple fecundity for both partner and couple-based models (p-trend=0.02 and p-trend=0.05, respectively). No associations were observed with couple fecundity when chemicals were modeled continuously. CONCLUSIONS: Higher quartiles of preconception urinary concentrations of MP and EP among female partners were associated with reduced couple fecundity in partner-specific and couple-based exposure models.