Combined exposure to PM(2.5) and PM(10) in reductions of physiological development among preterm birth: a retrospective study from 2014 to 2017 in China

BACKGROUND: Preterm birth (PTB) has been linked with ambient particulate matter (PM) exposure. However, data are limited between physiological development of PTB and PM exposure. METHODS: Trimester and season-specific PM exposure including PM(2.5) and PM(10) was collected from Jiaxing between January 2014 and December 2017. Information about parents and 3,054 PTB (gestational age < 37 weeks) outcomes such as weight (g), head circumference (cm), chest circumference (cm), height (cm) and Apgar 5 score were obtained from birth records. We used generalized linear models to assess the relationship between PTB physiological developmental indices and PM(2.5), PM(10) and their combined exposures. A binary logistic regression model was performed to assess the association between exposures and low birth weight (LBW, < 2,500 g). RESULTS: Results showed that there were 75.5% of low birth weight (LBW) infants in PTB. Decreased PM(2.5) and PM(10) levels were found in Jiaxing from 2014 to 2017, with a higher PM(10) level than PM(2.5) each year. During the entire pregnancy, the highest median concentration of PM(2.5) and PM(10) was in winter (61.65 ± 0.24 vs. 91.65 ± 0.29 μg/m(3)) followed by autumn, spring and summer, with statistical differences in trimester-specific stages. After adjusting for several potential factors, we found a 10 μg/m(3) increase in joint exposure of PM(2.5) and PM(10) during the entire pregnancy associated with reduced 0.02 week (95%CI: −0.05, −0.01) in gestational age, 7.9 g (95%CI: −13.71, −2.28) in birth weight, 0.8 cm in height (95%CI: −0.16, −0.02), 0.05 cm (95%CI: −0.08, − 0.01) in head circumference, and 0.3 (95%CI: −0.04, −0.02) in Apgar 5 score, except for the chest circumference. Trimester-specific exposure of PM(2.5) and PM(10) sometimes showed an opposite effect on Additionally, PM(2.5) (OR = 1.37, 95%CI: 1.11, 1.68) was correlated with LBW. CONCLUSION: Findings in this study suggest a combined impact of fine particulate matter exposure on neonatal development, which adds to the current understanding of PTB risk and health.