Associations Of Unconventional Natural Gas Development And Maternal Health Outcomes

Abstract

Background: Unconventional natural gas development (UNGD) has begun in several countries and has expanded rapidly in several regions of the USA. A recent study by our group found associations between gestational exposure to UNGD and preterm birth, reduced birth weight, and high-risk pregnancies. Aims: To evaluate associations of an index of UNGD, incorporating all phases and their overlap with gestation, with maternal health outcomes including gestational diabetes, preeclampsia/eclampsia, depression, and anxiety. Methods: We evaluated associations between residential exposure to UNGD and four maternal health outcomes among 9384 mothers linked to 10946 neonates in the Geisinger Health System between 2009 and January 2013. We estimated an index of cumulative exposure to UNGD with an inverse-distance squared model that incorporated distance to the mother's home; dates and durations of well pad development, drilling, and hydraulic fracturing; and production volume during pregnancy. Maternal characteristics were extracted from the electronic health record. We will use multilevel logistic regression to examine associations between UNGD index quartile and the four maternal health outcomes, while controlling for potential confounding variables. We will also assess mediation by maternal mental health on previously reported associations of UNGD exposure and birth outcomes. Results: In preliminary adjusted analysis, the UNGD index was not associated with gestational diabetes identified from diagnosis codes (n = 798). Older maternal age, overweight, and obesity and Hispanic ethnicity were significantly associated with code-identified gestational diabetes. Future analyses will identify gestational diabetes and preeclampsia/eclampsia using laboratory data and depression and anxiety using diagnosis codes, labor and delivery notes, and medications. Conclusions: As UNGD continues worldwide, we need to evaluate health in those living nearby, including outcomes in mothers and neonates.