Date of Award
Master of Public Health (MPH)
School of Public Health
Introduction: Low birthweight serves as a proxy risk factor for a number of conditions later in development. Of China’s urban centers, Lanzhou has long been considered one of the worst-affected cities by air pollution.
Objectives: This study uses spatial heterogeneity in air pollution exposure across addresses in Lanzhou and temporal heterogeneity resulting from the differential timing of pregnancy in the Lanzhou Birth Cohort to investigate the association between PM10 exposure and birthweight.
Methods: The study population consisted of 4,865 mother-child pairs from the Gansu Provincial Maternity and Child Care Hospital. Participants completed an epidemiological questionnaire and patient data were collected from hospital records. Environmental data from four monitoring stations were provided by the Gansu Provincial Environmental Monitoring Central Station. Linear regressions were used to model the relationship between mean PM10 exposure during the whole pregnancy and birthweight.
Results: The lowest PM10 exposure quartiles had a mean birthweight of 3396 g, compared to a mean birthweight of 3373 g for the highest PM10 exposure quartiles. A 10 µg/m3 increase in mean PM10 exposure during the 2nd trimester was associated with an 8 g (sd 2 g) decrease in birthweight (P=0.0002) and the same increase during the 3rd trimester was associated with a 4 g (sd 1 g) decrease in birthweight (P=0.0019). Mean PM10 exposure during the whole pregnancy was not found to have significant interactions with income, maternal BMI, newborn sex, or dietary factors.
Conclusion: PM10 exposure, especially during the 2nd and 3rd trimesters, may be associated with decreased birthweight. Though Lanzhou long topped lists of cities most affected by air pollution in China, the local government launched a major initiative in 2012 to significantly reduce air pollution presenting opportunities for natural experiments to understand the burden of air pollution. The findings of this study may serve as a reference for comparison of future results.
Wang, Dennis, "The Effect Of Spatiotemporally-Dependent Air Pollution Exposure On Birthweight In The Lanzhou Birth Cohort" (2016). Public Health Theses. 1312.