In utero exposure to extreme heat increases neonatal mortality

Area of Science:

• Environmental Health
• Climate Change Impacts
• Maternal and Child Health

Background:

• Sub-Saharan Africa (SSA) faces the world's highest neonatal mortality rates.
• Climate change is increasing extreme heat events in SSA, impacting vulnerable populations.
• The link between in-utero heat exposure and neonatal mortality in SSA is not well understood.

Purpose of the Study:

• To investigate the association between extreme heat exposure during pregnancy and neonatal mortality in SSA.
• To quantify the impact of heat exposure, considering humidity, on neonatal deaths.
• To identify socioeconomic factors influencing vulnerability to heat exposure.

Main Methods:

• Utilized granular data on extreme heat and birth records from 33 SSA countries.
• Employed nationally representative, repeated cross-sectional Demographic and Health Surveys.
• Applied a heat measure accounting for both temperature and humidity.

Main Results:

• A cumulative 150 °C increase in extreme heat exposure during pregnancy is linked to two additional neonatal deaths per thousand live births.
• Mothers with lower socioeconomic status or limited education experienced more severe negative impacts.
• Reduced prenatal care access may exacerbate the adverse effects of heat exposure.

Conclusions:

• In-utero exposure to extreme heat is a significant contributing factor to neonatal mortality in SSA.
• Climate change adaptation strategies must consider the heightened risks for vulnerable pregnant women and newborns.
• Policy interventions should focus on mitigating heat's impact and supporting at-risk populations.