The Relationship Between Air Pollution and Gestational Diabetes Incidence: A Systematic Review

Introduction: Gestational diabetes mellitus (GDM) is one of the most common complications occurring during pregnancy. This disorder is associated with adverse outcomes for mothers and their infants. Air pollution is one of the environmental stimuli that may predispose pregnant women to GDM. This systematic review examined studies on the relationship between air pollution and GDM incidence. Materials and Methods: In this systematic review, the PubMed, Web of Science, and Scopus databases, as well as Persian databases of SID, Irandoc, and Magiran, were searched for related English and Persian articles using appropriate keywords until September 11, 2021. Out of 36175 related articles in the initial search, 31 eligible studies were evaluated. The quality of the articles was assessed using the Newcastle-Ottawa scale. Results: The review included 29 cohort studies, a case-control study, and a cross-sectional study. The quality assessment results showed that of the 31 studies selected, 29 (93.5%) were high quality studies, and only two (6.5%) were moderate quality studies. PM2.5 pollutants followed by NO2 pollutants were the most examined in the studies. Conclusion: The results showed a direct relationship between air pollutants and GDM. The systematic review of the studies revealed that inflammation, oxidative stress, β-cell dysfunction, neurological, hormonal imbalance, intestinal microbiota imbalance, and insulin resistance may be involved in the association between air pollution and GDM.