Exposure to High Levels of Air Pollution During Pregnancy Significantly Increases Risk of Postpartum Depression

According to a new study led by the University of Southern California, high exposure to air pollution may increase a new mother’s risk of developing postpartum depression up to three years after birth.

For their study, the researchers examined a sample of mothers recruited by the Maternal and Developmental Risks from Environmental and Social stressors (MADRES) program at the Center for Environmental Health Disparities in the USC Keck School of Medicine. The majority of participants in the MADRES cohort identify as Hispanic or Latina. The authors followed 361 mothers from the start of their pregnancy through three years postpartum, surveying their depressive symptoms one, two, and three years after birth and tracking their weekly exposure to air pollutants.

Compared to women with low levels of exposure, women who were exposed to high levels of nitrogen dioxide in the second trimester of their pregnancy were 3.86 times more likely to experience postpartum depression for up to three years following birth. Similarly, women exposed to high levels of inhalable particle material during their second trimester were 3.88 times more likely to have postpartum depression.

The findings suggest that reducing exposure to air pollution during pregnancy, particularly the second trimester, should be a top priority in addressing postpartum depression disparities among Hispanic women. Furthermore, the authors stress that healthcare leaders need to prolong mental health screening and care beyond the typical 12 months postpartum time period.