Could BPA exposure in the womb cause obesity?

Research from the University of Melbourne has drawn a possible link between Bisphenol A (BPA) and later-life obesity.

The study, headed by Dr Mark Green from the Faculty of Science, looked at the impact of environmentally relevant levels of BPA on bovine embryos during early days post-fertilisation.

It found BPA — found in a wide range of everyday items including soft drink cans, cash register receipts and plastic bottles — significantly decreased the percentage of embryos developing further in vitro after just four days of exposure.

Exposure within the first week of pregnancy notably led to a substantial rise in the consumption of glucose — the embryo’s main food source.

This suggests BPA could lead to a predisposition to metabolic syndrome or obesity in adulthood, given that changes to the early embryo environment are known to alter later-life health and growth.

BPA is an endocrine disruptor, a chemical that impacts the hormonal system by interfering with the oestrogen pathway. It is one of the highest quantity man-made chemicals in the world.

Several studies have raised concerns about BPA’s potential to cause health problems, such as breast and prostate cancers, obesity and certain behavioural disorders.

Dr Green, a reproductive biologist, said the study suggests even short exposure to BPA at the embryo stage can have an impact.

“Our work shows even in the first week of pregnancy the development and, importantly, metabolism of an embryo can be perturbed,” he said.

Dr Green said previous studies have mainly investigated the effects of BPA at toxic levels or exposure during adulthood, and there have been a number of epidemiological studies that have identified an association between BPA and obesity in humans, but the mechanism and the timing of when during development and how this occurs was unclear.

“Now we can see that exposure to BPA levels found in the human population can increase glucose consumption in the embryo, which might suggest obesity later on,” he said.

“Our work highlights, for women trying to conceive, the importance of understanding how maternal exposure to environmental contaminants can have long-term impacts on a baby.”

The study has been published in Scientific Reports.