September 8, 2023

expert reaction to unpublished abstract and poster on air pollution and birth weight

An unpublished study presented at the European Respiratory Society International Congress 2023 looks at the relationship between high air pollution and low birth weight.

Dr George Savva, Senior Research Scientist at Quadram Institute Bioscience, said:

“These preliminary findings are consistent with many previous studies from around the world suggesting that higher levels of particulate air pollution are associated with low birth weight, and that access to green space is beneficial.  Without seeing the full report it is difficult to comment further on this work.”

Dr Rosie Cornish, Senior Research Fellow in Population Health Sciences at the Bristol Medical School, University of Bristol, said:

“This study shows that exposure to higher air pollution during pregnancy is associated with lower birthweight (on average) and living in a greener area during pregnancy is associated with higher birthweight (on average). However, it does not establish a causal link between pollution or greenness and birthweight. Thus, the statement that ‘Women exposed to air pollution give birth to smaller babies’ is misleading.

“It’s also worth noting that the abstract and the press release seem to contradict each other.  The abstract says ‘Air pollution exposure was associated with neither birth weight nor pre-term birth’, whereas the press release states ‘Women exposed to air pollution give birth to smaller babies’.  These statements are not consistent.

“A key issue is that women living in less green / more polluted areas almost certainly differ from those living in more green / less polluted areas in other key ways (for example, in terms of level of deprivation) and these factors might be the true underlying causes of the differences in birthweight. The researchers have taken account of some of these factors (education levels and several others) but it is likely that some differences have not been captured.

“It is certainly possible that exposure to air pollution and living in a greener area are direct or indirect causes of lower/higher birthweight, but it is impossible to tell with these data.”

Dr Meenakshi Choudhary, Senior Consultant in Reproductive Medicine, Newcastle upon Tyne Hospitals NHS Foundation Trust, said:

“The impact of air pollution on the reproductive health of women carries implications not just for their well-being but also for future generations. This study has shed light on one facet of this issue, suggesting a potential reduction in birth weight among babies born to mothers residing in less green areas.

“However, it’s important to emphasize that this study is currently presented as a poster abstract, lacking the comprehensive data needed for conclusive results. Robust evidence is crucial to establish a clear understanding of the effects.

“Urgent action is required from global policymakers and governments to address air pollution and its health consequences. Nevertheless, it’s essential to approach these findings with measured consideration. The observed difference in birth weight, while notable, was relatively small (27 grams).

“In the midst of rising concerns about air pollution’s impact on fertility, miscarriage and pregnancy outcomes, I’m currently leading a pilot feasibility study (in Newcastle, UK) funded by Theramex BIRTH grant, investigating the influence of air pollutants on fertility and IVF outcomes. This work aims to provide deeper insights into this critical area of reproductive health. This study is conducted in collaboration with Professor Anil Namdeo who has expertise in environmental air pollutants from Northumbria University.”

‘Preconception air pollution/greenness exposure and pregnancy outcomes: The Life-GAP Project’ by Robin Mzati Sinsamala et al. was presented at the European Respiratory Society International Congress 2023.

Declared interests

Rosie Cornish: None.

George Savva: I have no conflict of interest.

No others received.