Critical windows of greenness exposure during preconception and gestational periods in association with birthweight outcomes

Zhenchun Yang; Jiawen Liao; Yi Zhang; Yan Lin; Yihui Ge; Wu Chen; Chenyu Qiu; Kiros Berhane; Zhipeng Bai; Bin Han; Jia Xu; Yong Hui Jiang; Frank Gilliland; Weili Yan; Zhanghua Chen; Guoying Huang; Junfeng Jim Zhang

doi:10.1088/2752-5309/ad0aa6

Critical windows of greenness exposure during preconception and gestational periods in association with birthweight outcomes

Environ Res Health. 2024 Mar 1;2(1):015001. doi: 10.1088/2752-5309/ad0aa6. Epub 2023 Nov 16.

Authors

Zhenchun Yang¹, Jiawen Liao², Yi Zhang³, Yan Lin¹, Yihui Ge¹, Wu Chen², Chenyu Qiu², Kiros Berhane⁴, Zhipeng Bai⁵, Bin Han⁵, Jia Xu⁵, Yong Hui Jiang⁶, Frank Gilliland², Weili Yan³, Zhanghua Chen², Guoying Huang³, Junfeng Jim Zhang^{1

7}

Affiliations

¹ Duke Global Health Institute, Duke University, Durham, NC, United States of America.
² Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States of America.
³ Children's Hospital of Fudan University, Shanghai Key Laboratory of Birth Defect, Shanghai, People's Republic of China.
⁴ Department of Biostatistics, Mailman School of Public Health, Columbia University, New York, NY, United States of America.
⁵ State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, People's Republic of China.
⁶ Department of Genetics, Neuroscience, and Pediatrics, Yale University School of Medicine, New Haven, CT, United States of America.
⁷ Division of Environmental Science and Policy, Nicholas School of the Environment, Duke University, Durham, NC, United States of America.

Abstract

Few studies have examined the association between greenness exposure and birth outcomes. This study aims to identify critical exposure time windows during preconception and pregnancy for the association between greenness exposure and birth weight. A cohort of 13 890 pregnant women and newborns in Shanghai, China from 2016-2019 were included in the study. We assessed greenness exposure using Normalized Difference Vegetation Index (NDVI) during the preconception and gestational periods, and evaluated the association with term birthweight, birthweight z-score, small-for-gestational age, and large-for-gestational age using linear and logistic regressions adjusting for key maternal and newborn covariates. Ambient temperature, relative humidity, ambient levels of fine particles (PM_2.5) and nitrogen dioxide (NO₂) assessed during the same period were adjusted for as sensitivity analyses. Furthermore, we explored the potential different effects by urbanicity and park accessibility through stratified analysis. We found that higher greenness exposure at the second trimester of pregnancy and averaged exposure during the entire pregnancy were associated with higher birthweight and birthweight Z-score. Specifically, a 0.1 unit increase in second trimester averaged NDVI value was associated with an increase in birthweight of 10.2 g (95% CI: 1.8-18.5 g) and in birthweight Z-score of 0.024 (0.003-0.045). A 0.1 unit increase in an averaged NDVI during the entire pregnancy was associated with 10.1 g (95% CI: 1.0-19.2 g) increase in birthweight and 0.025 (0.001-0.048) increase in birthweight Z-score. Moreover, the associations were larger in effect size among urban residents than suburban residents and among residents without park accessibility within 500 m compared to those with park accessibility within 500 m. Our findings suggest that increased greenness exposure, particularly during the second trimester, may be beneficial to birth weight in a metropolitan area.

Keywords: NDVI; air pollutant; birthweight; greenness; preconception; pregnancy; urbanicity.

Abstract

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