Grants and Fellowships | 2014

46 Post-Doctoral Fellowships The Effect of BPA on Human Oocyte Maturation – In Vitro Study The main focus of this research was to investigate the effect of the environmental chemical, bisphenol A (BPA) on normal human oocyte (egg) development. Potential sources of BPA exposure include drinking water, air and dust, as well as polycarbonate baby bottles, tableware, white dental fillings and sealants and the resin lining of cans used in food and beverage products. BPA was detected in human fluids such as urine, serum, fetal serum, amniotic fluid and follicular fluid, the fluid that embeds the oocyte. Immature oocytes (GV) from patients undergoing IVF procedure, which would otherwise be discarded, were used following patient signed informed consent for donation of their discarded oocytes for research. Oocytes from only one cycle of each patient were included in the study. A total of 352 oocytes were cultured with 0, 20, 200 ng/ml or 20 µg/ml of BPA. Oocytes were then fixed and labeled for tubulin, actin and chromatin and assessed with confocal microscopy for their meiotic stage. Mature oocytes (MII) (n=175) were further classified according to their spindle configurations and patterns of chromosome alignment. We showed a decrease in the percentage of oocytes that normally developed (progressed to MII) as the BPA dose increased (p=0.002). As BPA dose increased, there was an increase in the percentage of oocytes that were degenerated (p=0.01) or that had undergone abnormal spontaneous activation (p=0.007). Among MII oocytes, as the BPA dose increased, there was a significant decrease in the incidence of bipolar spindles (p<0.0001) and aligned chromosomes (p=0.02). Research publications (1) Machtinger, R., Combelles, C.M., Missmer, S.A., Correia, K.F., Williams, P., Hauser, R., & Racowsky, C. (2013). Bisphenol-A and human oocyte maturation in vitro. Human Reproduction, 28 (10), 2735-2745. Fellow Ronit Machtinger Harvard University, USA Supervisors Catherine Racowsky and Russ Hauser 2010-2012