A Hot Pregnancy: Is Extreme Heat Exposure a Potential Determining Factor for Pre-term Births?

Abstract

Background: Preterm births are defined when an infant is born 37 weeks earlier than the gestational period, causing developmental delays or in severe cases infant mortality. With the global increase in heat temperatures, pregnant women classify as a vulnerable population to adverse health effects due to the heat. Objective: The objective of this literature review is to assess the relationship between increase in extreme heat temperatures and rates of preterm births in Canadian and American pregnant women. Methods: A structured literature review search was conducted through the University of Ottawa library databases using the keywords: preterm births and heat. Articles were refined by the inclusion and exclusion criteria providing a total of five articles deemed eligible for the literature review. Results: From the five eligible articles, three were case-crossover studies and the two remaining were time-to-event study and an observational cohort study. All five publications arrived to the same conclusion, stating a positive correlation between extreme heat exposure and preterm deliveries. Conclusion: An association has been proposed with the findings, however, a concrete conclusion has not been reached due to the lack of research present in the scientific community. Further investigation is needed to provide conclusive results.