Oral Presentation ESA-SRB 2023 in conjunction with ENSA

Low-level exposure to Bisphenol A and its alternatives has detrimental impacts on oocyte health   (#75)

Alexandra E Peters 1 2 , Emmalee A Ford 1 2 3 , Shaun D Roman 4 , Elizabeth G Bromfield 5 6 7 , Brett Nixon 6 7 , Kirsty G Pringle 1 2 , Jessie M Sutherland 1 2
  1. School of Biomedical Science and Pharmacy, College of Health, Medicine, and Wellbeing, University of Newcastle, Callaghan, NSW, Australia
  2. Mothers and Babies Research Program, Hunter Medical Research Institute , New Lambton Heights, NSW, Australia
  3. The Research Centre, Family Planning Australia, Newington, NSW, Australia
  4. NSW Health Pathology, Newcastle, NSW, Australia
  5. School of BioSciences, Faculty of Science, Bio21 Institute, The University of Melbourne, Parkville, VIC, Australia
  6. School of Environmental and Life Sciences, College of Engineering, Science, and Environment, University of Newcastle, Callaghan, NSW, Australia
  7. Infertility and Reproduction Program, Hunter Medical Research Institute, New Lambton Heights, NSW, Australia

Bisphenol A (BPA) is an endocrine disrupting chemical and component of plastic materials, including food packaging, ubiquitously contaminating ecosystems and human populations. BPA can elicit an array of damaging health effects and alarmingly, emerging 'BPA-free' alternatives mirror these harmful effects. Bisphenol exposure can negatively impact female fertility, damaging both the ovary and oocytes therein. Such damage can, in turn, diminish reproductive capacity, pregnancy success, and offspring health. Despite global government regulations in place to indicate ‘safe’ BPA exposure levels, these policies have neglected to consider the effects of BPA and BPA alternatives on oocyte health. To address this discrepancy, we conducted a scoping review to evaluate evidence on the effects of BPA/BPA alternatives on five standardised parameters of oocyte health. Four databases (Medline, Embase, Scopus, and Web of Science) were searched to capture studies assessing mammalian oocyte health post-bisphenol exposure. After screening, 106/3147 studies were included. Of the in vitro exposure studies, 96.2% (26/27) and 93.8% (15/16) found at least one adverse oocyte effect using BPA or BPA alternatives, respectively. These included increased meiotic cell cycle arrest, altered morphology, and abnormal meiotic spindle/chromosomal alignment. In vivo, 82.9% (29/35) of studies on BPA and 92.3% (12/13) on BPA alternatives documented adverse effects on follicle development, morphology, or spindle/chromosome alignment. Importantly, these effects were recorded using levels below those deemed ‘safe’ for human exposure. Over half (11/21) of all human observational studies correlated higher urinary BPA levels with reduced antral follicle counts or oocyte yield in IVF patients. These data highlight the detrimental impacts of low-level BPA and BPA alternative exposure, contributing to poor oocyte quality and reduced fertility. In addition, this study serves as a valuable resource to researchers, providing key recommendations on study design, reporting elements, and endpoint measures to strengthen future studies and promote revision of current guidelines.