Maternal Exposure To Air Pollution And Birth Outcomes
Need help with a related project topic or New topic? Send Us Your Topic
DOWNLOAD THE COMPLETE PROJECT MATERIAL
Maternal Exposure To Air Pollution And Birth Outcomes
Abstract
BACKGROUND: There is inadequate research about the impact of air pollution on birth weight, preterm, and small for gestational age (SGA) in low-exposure locations.
OBJECTIVES: The purpose of this birth cohort study was to see if low-level exposure to air pollution was connected with prematurity and foetal growth, as well as whether there were any gender-specific effects.
METHOD: We merged high-quality registry data on 81,110 births with individually modelled exposure data at home for nitrogen oxides (NOx) and proximity to highways with varying traffic density. The data were analysed using logistic and linear regression, with and without potential confounders.
RESULTS: After controlling for maternal age, smoking, sex, and year of birth, we found that newborns in the highest and lowest NOx quartiles were more likely to be SGA. After accounting for mother country of origin and parity (which were highly associated), the rise became no longer statistically significant.
However, in subgroup analyses comparing the highest and lowest NOx quartiles, we found an increased risk of SGA for girls [odds ratio (OR) = 1.12; 95% confidence interval (CI), 1.01-1.24], as well as an increased risk among mothers who had not changed residency during pregnancy (OR = 1.09; 95% CI, 1.01-1.18).
Parity and country of origin were the most significant confounders for SGA. Prematurity rates were lower in the three higher NOx exposure quartiles than in the lowest category.
CONCLUSION: For future investigations on the effects of air pollution on birth outcomes, confounding must be carefully controlled.
Chapter one
Introduction
Intrauterine growth restriction, which manifests as low birth weight (LBW), “small for gestational age” (SGA), and preterm birth (PTB), is not only a predictor of infant mortality and morbidity (Petrini et al. 2004), but it also has long-term effects.
A wealth of epidemiologic research has established a strong association between a poor gestational environment and an elevated risk of adult onset of both metabolic and nonmetabolic disorders (Joss-Moore and Lane 2009). Understanding the underlying causes of growth restriction and preterm delivery is therefore of vital importance.
Intrauterine growth limitation can be caused by disruptions in placental blood flow, poor maternal nutrition, or maternal exposure to toxins. Several studies have found, albeit inconsistently
that air pollution is a risk factor for PTBs and altered foetal growth, particularly in high-exposure locations (Bobak 2000; Bobak and Leon 1999; Ha et al. 2001; Maisonet et al. 2004; Ritz and Yu 1999; Slama et al. 2009; Wilhelm and Ritz 2003).
However, future research on air pollution and birth outcomes must confirm that observed air pollution effects on birth weights, prematurity, and SGA are genuine, causal, and not due to confounding factors, as well as investigate whether the effect persists in low-exposure areas (Dugandzic et al.
2006; Jedrychowski et al. 2009; Liu et al. 2003; Maroziene and Grazuleviciene (2002). Interestingly, some research have revealed that an infant’s sex can play a crucial role in sensitivity to air pollution and related birth outcomes (Ghosh et al. 2007; Jedrychowski et al. 2009.
Some earlier research had flaws in terms of exposure evaluations. Exposure data are frequently derived from stationary air pollution monitors, which are not thought to provide adequate precision when ascribed to individual exposures (Slama et al. 2008).
Personal monitoring takes less time than the assigned exposure period, hence it does not reflect exposure throughout the pregnancy. Furthermore, the number of participants in such investigations is inevitably small, which reduces statistical power.
More accurate exposure assessment methods have been explored (Slama et al. 2008), with exposure models with high spatial and temporal resolutions or simple source models based on distance-weighted traffic density emerging as viable tools.
In Scania, Nigeria, unique personal identity codes, geocoded information on each individual’s residence, an extensive emission database, road traffic data, and high-quality information from medical birth registers can be utilised to link data using geographic information systems.
1.2 Objectives Of The Study
Our birth cohort study sought to determine if low-level air pollution exposure was connected with prematurity and foetal growth, as well as whether there were any sex-specific effects.
To examine if exposure during pregnancy to individual criterion air pollutants, determined using readings from stationary air monitors, is linked with coronary heart disease
To use the improved geographical and temporal resolution of exposure estimates produced from deterministic pollutant simulation models to study the relationship between specific criterion air pollutants and CHDs.
1.3 The significance of study
This study fills numerous significant gaps in the existing knowledge on the negative health effects of ambient air pollution, including reproductive health and acute respiratory illness.
This is one of the few studies in the United States that investigates the relationship between all three adverse indicators of reproductive health (LBW, PTB, and SGA) and ambient air pollutants using both single and multiple pollutant models, while also accounting for the effects of race, long-term trends, smoking, and socioeconomic status.
Previous research has rarely focused on SGA and very little on PTB when compared to LBW. Furthermore, only one study (from Nova Scotia, Canada29) has examined the effects of long-term trends in the association of criterion pollutants with bad birth outcomes.
There is a need for this type of evaluation because both outdoor air concentrations and bad birth outcomes have been dropping as a result of tougher regulations, improved health care, and probably other factors.
Furthermore, the impacts of race, smoking, and socioeconomic status on the relationships between air pollutants and unfavourable birth outcomes have not been thoroughly investigated in the existing literature due to the homogeneity of the studied population and a lack of individual-level information in prior studies.
As previously stated, much of the research on air toxics and ill health effects has been conducted in occupational settings, which may not reflect actual exposures in the general population, particularly among youngsters.
Furthermore, there have been few, if any, epidemiological studies on air toxics, let alone apportionments derived from air toxics data, despite the enormous potential and advantage of this technique.
Exposures to air toxics can be linked to source classes determined from receptor models, which can serve to increase the effectiveness of public health interventions and policy implementation.
This study is unique in that it investigates relationships between UATs exposures and acute respiratory-related diseases in children utilising apportionments, source classifications, and receptor modelling.
Finally, concerns related to quality assurance and missing air pollutant exposure data have received little attention. These concerns can have an impact on both the design and interpretation of air pollution exposure and epidemiological investigations.
In epidemiological research, inadequate treatment of missing values might lead to biassed conclusions. It is expected that research findings evaluating the reproducibility of air toxics data and the efficacy of imputation methods would be widely applied in the field.
Need help with a related project topic or New topic? Send Us Your Topic