Introduction: The attention on environmental impact on human health is rising. But, the association between particulate matter 2.5 and birth weight is still not acknowledged in the global burden of diseases, and the association has not yet been studied in the Philippines. The aim was to explore how increasing/decreasing concentrations of particulate matter 2.5 in pregnant women’s residence area was associated with the risk of having a child with low birth weight in the Philippines.

Method: 1462 women pregnant in 2016 from the Demographic and Health Survey done in the Philippines in 2017 were analyzed by exposure to particulate matter 2.5 in their residence area. Particulate matter 2.5 was derived from the DIMAQ model, which estimated the annual mean exposure based on a mix of methods. A logistic regression adjusted for demographic variables and variables important for fetal growth, and the birth season was done.

Results: The results of the logistic regression when adjusted for all variables showed that the non-statistically significant odds of low birth weight in the children from to the particulate matter 2.5 categories: 7-10 μg/m3, 11-14 μg/m3, and 15-18 μg/m3 were respectively 21% lower (CI: 0.42-1.50), 33% lower (CI: 0.39-1.21) and 34% lower (CI: 0.39-1.14) compared to the highest exposure category of 19-22 μg/m3.

Discussion: The study had several limitations in regard to the study design, especially in dealing with seasonal changes in low birth weight. Yet, the study did not disagree with the results from similar studies done in other countries or globally.