Urinary bisphenol A concentrations and in vitro fertilization outcomes among women from a fertility clinic

Bisphenol A (BPA) is a widespread environmental endocrine disrupting chemical. Although many animals and in vitro studies reported that BPA may affect female fertility through the effect on maturing oocytes and meiotic cell division, but the data from human studies are limited and inconclusive. The study was conducted to examine the association between urinary BPA concentration and in vitro reproductive outcomes (metaphase II (MII) oocyte yield, top quality embryo, fertilization rate, implantation rate and clinical pregnancy) among women from an infertility clinic. The study participants were enrolled in the Infertility Center in Poland. 450 women aged 24-44 (n = 674 IVF cycles) provided urine samples. The urinary concentrations of BPA were evaluated using validated gas chromatography ion-tap mass spectrometry method. Clinical outcomes of IVF treatment were abstracted from patients electronic chart records. To assess the relationship between urinary BPA concentrations early examined reproductive outcomes generalized linear mixed models were used. The detection rate of BPA in urine samples was 98% and the geometric mean 1.59 +/- 2.15 ng/ml. A significant decrease was observed between urinary concentration of BPA and implantation (p = 0.04) and decreased MII oocyte count (p = 0.03). There was no association between other examined IVF outcomes: embryo quality, fertilization rate and clinical pregnancy and BPA exposure. Exposure to BPA may have a negative effect during the early stages of human development. The studies among the larger and more diverse population are needed to confirm the results.