The association between phthalates exposure and serum reproductive hormones in Taiwanese fertile and infertile men

Abstract

Background: Phthalates have demonstrated the adverse effects on androgen-regulated reproductive function in animals. Epidemiological studies have reported inconsistent evidences between phthalates exposure and human reproductive function, including reproductive hormones and semen quality. Aims: To investigate the general exposures of Taiwanese fertile and infertile menand estimate the potential effects on reproductive functions. Methods:This case-control study was carried out from 2010 through 2012. 139 men were recruited through infertility clinics and 25 men were recruited form obstetrics clinics.After signing informed consents, urine, serum and semen samples were collected. Urinary phthalate monoesters and secondary metabolites were analyzed by HPLC-MS/MS. The semen qualities like semen volume, sperm concentration, motility and morphology and reproductive hormones, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone (total T), free testosterone (fT), inhibin B and estradiol (E2) and sex hormone-binding globulin (SHBG) were measured. Results: After adjusted for creatinine, urinary MEP, MnBP, MEHHP, MECPP concentrations of infertile men with below or above WHO semen reference levels were significant higher than fertile men. After adjusted age, BMI, current smoking and drinking, total T was inversely associated with urinary MMP concentrations (p<0.001) and significantly negative associations between inhibin B and urinary DEHP metabolites as well as the ?DEHP (p<0.05) were found. Urinary MiBP and MBzP concentrations were negatively associated with fT (p<0.05). Significant trend test between ?DEHP and inhibin B, E2 were found (p<0.05). Conclusions:Our results suggest DEHP, DMP, DBP and BBzP exposures are robustly associated with minor alterations of some reproductive steroid hormones in men. Further research is needed to confirm these findings.