The perils of climate change: In utero exposure to temperature variability and birth outcomes in the Andean region

- We explore the effect of in utero exposure to temperature variability on birth outcomes.
- We focus on three developing countries in the Andean region.
- Increasing temperature variability during pregnancy reduces birth weight by 20 g.
- Temperature variability increases the incidence of low birth weight.
- Evidence suggests that food insecurity and reduced health care explain the results.

The discussion on the effects of climate change on human activity has primarily focused on how increasing temperature levels can impair human health. However, less attention has been paid to the effect of increased climate variability on health. We investigate how in utero exposure to temperature variability, measured as the fluctuations relative to the historical local temperature mean, affects birth outcomes in the Andean region. Our results suggest that exposure to a temperate one standard deviation relative to the municipality's long-term temperature mean during pregnancy reduces birth weight by 20 g. and increases the probability a child is born with low birth weight by a 0.7 percentage point. We also explore potential channels driving our results and find some evidence that increased temperature variability can lead to a decrease in health care and increased food insecurity during pregnancy.