Preconception air pollution exposure and glucose tolerance in healthy pregnant women in a middle-income country

Abstract

Background Preconception exposure to air pollution has been associated with glucose tolerance during pregnancy. However, the evidence in low and middle-income countries (LMICs) is under debate yet. Therefore, this study aimed to assess the relationship between exposure to ambient particulate matter (PM) and traffic indicators with glucose tolerance in healthy pregnant women in Sabzevar, Iran (2019). Methods Two-hundred and fifty healthy pregnant women with singleton pregnancies and 24–26 weeks of gestations participated in our study. Land use regression (LUR) models were applied to estimate the annual mean of PM1, PM2.5 and PM10 at the residential address. Traffic indicators, including proximity of women to major roads as well as total streets length in 100, 300 and 500 m buffers around the home were calculated using the street map of Sabzevar. The oral glucose tolerance test (OGTT) was used to assess glucose tolerance during pregnancy. Multiple linear regression adjusted for relevant covariates was used to estimate the association of fasting blood glucose (FBG), 1-h and 2-h post-load glucose with PMs and traffic indicators. Results Exposure to PM1, PM2.5 and PM10 was significantly associated with higher FBG concentration. Higher total streets length in a 100 m buffer was associated with higher FBG and 1-h glucose concentrations. An interquartile range (IQR) increase in proximity to major roads was associated with a decrease of − 3.29 mg/dL (95% confidence interval (CI): − 4.35, − 2.23, P-value < 0.01) in FBG level and − 3.65 mg/dL (95% CI, − 7.01, − 0.28, P-value = 0.03) decrease in 1-h post-load glucose. Conclusion We found that higher preconception exposure to air pollution was associated with higher FBG and 1-h glucose concentrations during pregnancy.

Exposure to air pollutant mixture and gestational diabetes mellitus in Southern California: Results from electronic health record data of a large pregnancy cohort

“…Air pollution exposure during pregnancy may also affect the development of GDM by similar mechanisms ( Ben-Haroush et al, 2004 ). The emerging evidence indicates that higher preconception exposure to air pollution might be associated with elevated blood glucose levels associated with increased insulin resistance and GDM development ( Najafi et al, 2020 ). An increasing number of epidemiological studies have examined the relationship between air pollution exposure and the risk of GDM ( Choe et al, 2019 ; Choe et al, 2018 ; Fleisch et al, 2014 ; Fleisch et al, 2016 ; Hu et al, 2015 ; Jo et al, 2019b ; Malmqvist et al, 2013 ; Padula et al, 2019 ; Pan et al, 2017 ; Pedersen et al, 2017 ; Robledo et al, 2015 ; Shen et al, 2017 ; Yu et al, 2020 ; Zhang, et al, 2020a ; Zheng et al, 2020 ), although conclusions are inconsistent regarding the effects of different air pollutants and exposure windows.…”

Prenatal Exposure to Ambient Air Pollution and Epigenetic Aging at Birth in Newborns

“…In the current study, we identified that exposure to PM 10 during the 6–11 weeks prior to conception was significantly inversely associated with epigenetic aging at birth. Exposure to PM during preconception has been linked to gestational diabetes mellitus, inflammation during pregnancy, and fetal growth ( Robledo et al, 2015 ; Nachman et al, 2016 ; Najafi et al, 2020 ), suggesting that preconception exposures may affect the growth and development of the placenta and the fetus. Findings from a Chinese study using weekly DLMs showed that exposure to PM 2.5 during the 1–9 weeks prior to conception was associated with fetal undergrowth ( Chen et al, 2022 ).…”

Environmental health influences in pregnancy and risk of gestational diabetes mellitus: a systematic review

“…Overall, the most articles pointed out that exposure to air pollution (through PM 2.5 [98-100, 105, 107, 118-121], PM 10 [98,100,119,121], PM 1 [121], BC [98], NO 2 [119], CO [119], SO 2 [100]) was able to increase blood glucose levels in pregnant women. In n = 7 of n = 9 studies, air pollution was significantly associated (p < 0.05 [98,99,105,119,120], p < 0.01 [107,121]) with elevated fasting blood glucose concentrations. The remaining n = 2 studies by Fleisch et al (n = 2.093) [118] and Lin et al…”