Correlation Between Bisphenol A And Polycystic Ovary Syndrome

1 BACKGROUNDPolycystic Ovary Syndrome(PCOS)is one of the most common gynecological endocrine diseases in women of reproductive age.It is clinically characterized by"persistent anovulation,hyperandrogenism,and polycystic ovarian changes",often accompanied by insulin resistance and obesity.PCOS may be caused by the synergistic effect of certain genetic and environmental factors.Bisphenol A(BPA),an environmental endocrine disrupter,is widely distributed in our daily life.Several studies have shown that the concentration of BPA in peripheral blood,urine and follicular fluid of PCOS patients is significantly higher than that of normal people.BPA may increase the metabolic risk of PCOS patients by promoting obesity,hyperinsulinemia,insulin resistance,dyslipidemia and elevated androgen levels.2 OBJECTIVES(1)Compare the difference of BPA concentration and related metabolic indexes between PCOS group and non-PCOS group.(2)To explore the effect of different levels of BPA internal exposure on assisted reproductive outcomes in PCOS patients.3 METHODS(1)Meta-analysis:The database was searched by the subject words " Polycystic Ovary Syndrome " and "Bisphenol A" and the key words.The study was screened according to the inclusion and exclusion criteria,and then the quality of the study and the risk of bias were evaluated.Finally,the data were extracted and the meta-analysis was performed using RevMan5.4.1 software.(2)Retrospective cohort study:A total of 334 patients who underwent IVF/ICSI for the first time in the Reproductive Center of Nanfang Hospital from January 2017 to December 2020 were enrolled.After excluding 57 patients over 40 years old,with decreased ovarian function,and 3 patients with missing data,117 patients with PCOS and 157 patients with normal ovarian function were finally included in the study.The median urinary BPA level of all patients was used as the cut-off value,and the subjects were divided into four groups:PCOS with high BPA exposure group(denoted as group Al),PCOS with low BPA exposure group(denoted as group A2),non-PCOS with high BPA exposure group(denoted as group B1),non-PCOS with low BPA exposure group(denoted as group B2).The general conditions and outcomes of assisted reproductive technology in each group were compared.Finally,multivariate regression was used to correct confounding factors for further analysis.4 RESULTS(1)Meta-analysis:A total of 11 studies involving 727 PCOS patients and 607 controls were included.The results showed that the level of BPA in PCOS group was significantly higher than that in control group(SMD=1.95,95%CI(1.08,2.83),P<0.001).The results of subgroup analysis showed that the heterogeneity in the high BMI group and the high HOMA-IR group was 0%,and the level of BPA in the PCOS group was higher,and the difference was statistically significant.(2)Retrospective cohort study:A total of 274 patients were included.The creatinine-corrected urinary BPA concentration was 2.70(4.49)(μmol/mol Cr)in PCOS group and 0.83(1.37)(μ mol/mol Cr)in non-PCOS group,and the difference was statistically significant.There were significant differences in basal luteinizing hormone,basal follicle stimulating hormone,basal testosterone,total antral follicle counting,ovulation induction protocol,Mature egg rate,normal fertilization rate,high-quality embryo rate,implantation rate,and clinical pregnancy rate among the four groups(all P<0.05).Multivariate regression analysis showed that PCOS and BPA exposure level were the influencing factors of high-quality embryo rate.BPA exposure level is an influencing factor of clinical pregnancy rate.5 CONCLUSIONS(1)The level of BPA internal exposure in PCOS patients was higher than that in non-PCOS patients,and the level of BPA was correlated with higher body mass index and higher HOMA index.(2)Higher internal exposure level of BPA may have adverse effects on the assisted reproductive outcomes of PCOS and non-PCOS patients,especially on the high-quality embryo rate of PCOS patients.