The impact of heat exposure on reduced gestational age in pregnant women in North Carolina, 2011-2015.

Journal Article (Journal Article)

Research on the impact of heat on pregnant women has focused largely on outcomes following extreme temperature events, such as particular heat waves or spells of very cold weather on pregnant women. Consistently, the literature has shown a statistically significant relationship between heat with shortened gestational age with studies concentrated largely in the western states of the USA or other nations. The association between heat and shortened gestational age has not been examined in the Southeastern US where maternal outcomes are some of the most challenging in the nation. Unlike previous studies that focus on the impacts of a single heat wave event, this study seeks to understand the impact of high heat over a 5-year period during the annual warm season (May-September). To achieve this goal, a case-crossover study design is employed to understand the impact of heat on preterm labor across regions in North Carolina (NC). Temperature thresholds for impact and the underlying relationships between preterm labor and heat are investigated using generalized additive models (GAM). Gridded temperature data (PRISM) is used to establish exposure classifications. The results reveal significant impacts to pregnant women exposed to heat with regional variations. The exposure variable with the most stable and significant result was minimum temperature, indicating high overnight temperatures have the most impact on preterm birth. The magnitude of this impact varies across regions from a 1% increase in risk to 6% increase in risk per two-degree increment above established minimum temperature thresholds.

Full Text

Duke Authors

Cited Authors

  • Ward, A; Clark, J; McLeod, J; Woodul, R; Moser, H; Konrad, C

Published Date

  • December 2019

Published In

Volume / Issue

  • 63 / 12

Start / End Page

  • 1611 - 1620

PubMed ID

  • 31367892

Pubmed Central ID

  • 31367892

Electronic International Standard Serial Number (EISSN)

  • 1432-1254

International Standard Serial Number (ISSN)

  • 0020-7128

Digital Object Identifier (DOI)

  • 10.1007/s00484-019-01773-3


  • eng