Maternal Ambient Exposure to Atmospheric Pollutants during Pregnancy and Offspring Term Birth Weight in the Nationwide ELFE Cohort

Prenatal PM2.5 exposure increases the risk of adverse pregnancy outcomes: evidence from meta-analysis of cohort studies

Adverse pregnancy outcomes (APOs) are a significant cause of fetal death. A wide range of maternal psychological, social, and environmental factors may contribute to these outcomes. Mounting epidemiological studies have indicated that PM2.5 may result in these unfavorable consequences. Previously published meta-analyses have been updated and extended. Cohort studies were searched from three databases (up to July 24, 2023), and their quality was assessed by Newcastle-Ottawa Scale (NOS). Publication bias was examined by Egger's test and funnel plot. Despite a large number of studies showing similar results, the inconsistencies between these findings require careful generalization before concluding. This meta-analysis included 67 cohort studies from 20 countries, and the findings revealed that maternal PM2.5 exposure and five APOs were correlated significantly throughout pregnancy: preterm birth (PTB) (RR = 1.05; 95% CI: 1.03, 1.07); low birth weight (LBW) (RR = 1.02; 95% CI: 1.01, 1.04); small for gestational age (SGA) (RR = 1.03; 95% CI: 1.01, 1.04); stillbirth (RR = 1.24; 95% CI: 1.06, 1.45); and change in birthweight (weight change = -6.82 g; 95% CI: -11.39, -2.25). A positive association was found between APOs and PM2.5 exposure in this meta-analysis, and the degree of increased risk of APOs varied due to different gestation periods. Therefore, it is necessary to protect pregnant women at specific times.

Environmental exposure to outdoor artificial light at night during pregnancy and fetal size: A prospective cohort study

BACKGROUND

Previous studies suggested outdoor artificial light at night (ALAN) exposure may contribute to children and adult obesity, but less is known about the associations of outdoor ALAN exposure during pregnancy with fetal size.

METHODS

From 2015 to 2021, 6210 mother-child pairs were included. Average outdoor ALAN levels during pregnancy were measured using satellite imaging data. Fetal biparietal diameter, head circumference, abdominal circumference (AC), and femur length were measured before delivery with ultrasonography. We also collected anthropometric birth outcomes, including birth length, birth weight, macrosomia, low birth weight, small for gestational age, and large for gestational age at delivery. Multivariable linear regression models and binary logistic regression models were used to examine the potential associations of outdoor ALAN with fetal size adjusting for a broad set of potential confounds.

RESULTS

An IQR (14.87 nW/cm²/sr) increase in outdoor ALAN during pregnancy was associated with 1.30 (β = 1.30, 95 % CI: 0.31,2.29) higher AC percentiles and 13 % (OR = 1.13, 95 % CI: 1.00,1.27) higher odds of macrosomia after adjusting confounders. In sex stratification analysis, an IQR (14.87 nW/cm²/sr) increase in outdoor ALAN during pregnancy was associated with 1.65 (β = 1.65, 95 % CI: 0.24,3.06) higher fetal AC percentiles and 27 % (OR = 1.27, 95 % CI: 1.06,1.53) higher odds of macrosomia in females.

CONCLUSIONS

Our findings suggest that higher outdoor ALAN exposure during pregnancy is associated with larger fetal AC and a higher risk of macrosomia, particularly in the female fetus. Future studies are needed to verify these preliminary findings and identify potential mechanisms for the association.

Personal exposure to PM2.5 oxidative potential and its association to birth outcomes

BACKGROUND

Prenatal exposure to fine particulate matter (PM2.5) assessed through its mass concentration has been associated with foetal growth restriction in studies based on outdoor levels. Oxidative potential of PM2.5 (OP) is an emerging metric a priori relevant to mechanisms of action of PM on health, with very limited evidence to indicate its role on birth outcomes.

OBJECTIVES

We investigated the association of OP with birth outcomes and compared it with that of PM2.5 mass concentration.

METHODS

405 pregnant women from SEPAGES cohort (Grenoble area) carried PM2.5 personal dosimeters for one or two one-week periods. OP was measured using dithiothreitol (DTT) and ascorbic acid (AA) assays from the collected filters. Associations of each exposure metric with offspring weight, height, and head circumference at birth were estimated adjusting for potential confounders.

RESULTS

The correlation between PM2.5 mass concentration and [Formula: see text] was 0.7. An interquartile range increase in .. was associated with reduced weight (adjusted change, -64 g, -166 to -11, p = 0.02) and height (-4 mm, -6 to -1, p = 0.01) at birth. PM2.5 mass concentration showed similar associations with weight (-53 g, -99 to -8, p = 0.02) and height (-2 mm, -5 to 0, p = 0.05). In birth height models mutually adjusted for the two exposure metrics, the association with [Formula: see text] was less attenuated than that with mass concentration, while for weight both effect sizes attenuated similarly. There was no clear evidence of associations with head circumference for any metric, nor for [Formula: see text] with any growth parameter.

IMPACT

PM2.5 pregnancy exposure assessed from personal dosimeters was associated with altered foetal growth. Personal OP exposure was associated with foetal growth restrictions, specifically decreased weight and height at birth, possibly to a larger extent than PM2.5 mass concentration alone. These results support OP assessed from DTT as being a health-relevant metric. Larger scale cohort studies are recommended to support our findings.