Climate extremes and the length of gestation

Although more extreme heat conditions have been predicted for the future, there is little information available on the potential impact of such conditions on pregnancy length. Dadvand et al. CREAL researchers investigated the impact of maternal short-term exposure to extreme ambient heat on the length of pregnancy based on a cohort of 7,585 births that occurred during 2001–2005 in Barcelona, Spain.

They applied three indicators of extreme heat conditions based on exposure to an unusually high heat–humidity index, and developed a two-stage analysis to quantify the change in pregnancy length after maternal exposure to extreme heat conditions, adjusting for a range of covariates.

Extreme heat was associated with a reduction in the average gestational age of children delivered the next day, suggesting an immediate effect of this exposure on pregnant women. The authors conclude that further studies are required to confirm these findings in different settings.

Source: Environmental Health Perspectives