The relationship between air pollution and preeclampsia with gestational hypertension; A systematic review

Introduction: The effects of air pollution on gestational hypertension and preeclampsia have been reported in a number of studies. Exposure to air pollutants is associated with adverse maternal and fetal consequences. In the present study, we conducted a systematic review on the relevant studies with the aim of determining the relationship between air pollution and gestational hypertension or preeclampsia. Methods: In this study, a review systematic was conducted to obtain relevant studies from the English databases Pubmed, Scopus, Web of science, , Cochrane library, Embase from the beginning of 2014 to the end of31 december 2019 with English keywords air pollution,hypertension during pregnancy and preeclampsia with all possible search combinations. Inclusion criteria: Cohort or case control articles, the target population of pregnant women, is considered one of the air pollutants and its relationship with preeclampsia or gestational hypertension. Exclusion criteria: review and meta-analysis, animal and genetic studies The quality of the articles was evaluated using the Strobe checklist. Results: out of 581 articles, 21 articles that had inclusion criteria were examined. 8 studies considered gestational hypertension only, 5 studies considered preeclampsia, and 8 studies both considered outcome. Each of these studies has considered a range of pollutants to be exposed and their relationship to pregnancy inducted hypertension or preeclampsia were investigated. Which had 18 articles good and excellent quality and 3 articles poor quality.8 studies reported gestational hypertension as outcome, 4 studies reported preeclampsia alone, and nine studies examined both outcomes. Conclusion: The results ofmost studies showned association between gestational hypertension or preeclampsia. While a number of studies have reported conflicting results on the effect of some air pollutants with preeclampsia or hypertension during pregnancy(HDP).Therefore, it is suggested that further cohort or case control studies be conducted in this area, in different countries around the world.