Association of Antepartum and Postpartum Air Pollution Exposure With Postpartum Depression in Southern California
This study found that exposure to air pollution during pregnancy and after giving birth was associated with a higher risk of postpartum depression. Specifically, exposure to ozone and particulate matter were linked to increased risk. Identifying and addressing these environmental risk factors is important for improving maternal mental health.
College of Health researcher(s)
College unit(s)
Highlights
Key Points
Question
Is maternal ambient air pollution exposure associated with increased risks of postpartum depression (PPD)?
Findings
In this cohort study of 340 679 pregnant women, antepartum and postpartum exposures to ozone, particulate matter less than or equal to 10 μm, and particulate matter less than or equal to 2.5 μm and its constituents (organic matter and black carbon) were associated with increased risks of PPD.
Meaning
These findings suggest that long-term antepartum and postpartum air pollution exposure is a potentially modifiable environmental risk factor for PPD and an important public health issue to address for improved maternal mental health.
Abstract
Importance
Women are especially vulnerable to mental health matters post partum because of biological, emotional, and social changes during this period. However, epidemiologic evidence of an association between air pollution exposure and postpartum depression (PPD) is limited.
Objective
To examine the associations between antepartum and postpartum maternal air pollution exposure and PPD.
Design, Setting, and Participants
This retrospective cohort study used data from Kaiser Permanente Southern California (KPSC) electronic health records and included women who had singleton live births at KPSC facilities between January 1, 2008, and December 31, 2016. Data were analyzed between January 1 and May 10, 2023.
Exposures
Ambient air pollution exposures were assessed based on maternal residential addresses using monthly averages of particulate matter less than or equal to 2.5 μm (PM2.5), particulate matter less than or equal to 10 μm (PM10), nitrogen dioxide (NO2), and ozone (O3) from spatial interpolation of monitoring station measurements. Constituents of PM2.5 (sulfate, nitrate, ammonium, organic matter, and black carbon) were obtained from fine-resolution geoscience-derived models based on satellite, ground-based monitor, and chemical transport modeling data.
Main Outcomes and Measures
Participants with an Edinburgh Postnatal Depression Scale score of 10 or higher during the 6 months after giving birth were referred to a clinical interview for further assessment and diagnosis. Ascertainment of PPD was defined using a combination of diagnostic codes and prescription medications.
Results
The study included 340 679 participants (mean [SD] age, 30.05 [5.81] years), with 25 674 having PPD (7.54%). Increased risks for PPD were observed to be associated with per-IQR increases in antepartum and postpartum exposures to O3 (adjusted odds ratio [AOR], 1.09; 95% CI, 1.06-1.12), PM10 (AOR, 1.02; 95% CI, 1.00-1.04), and PM2.5 (AOR, 1.02; 95% CI, 1. 00-1.03) but not with NO2; PPD risks were mainly associated with PM2.5 organic matter and black carbon. Overall, a higher risk of PPD was associated with O3 during the entire pregnancy and postpartum periods and with PM exposure during the late pregnancy and postpartum periods.
Conclusions and Relevance
The study findings suggest that long-term exposure to antepartum and postpartum air pollution was associated with higher PPD risks. Identifying the modifiable environmental risk factors and developing interventions are important public health issues to improve maternal mental health and alleviate the disease burden of PPD.