Rising heat exposure threatens maternal and newborn health

With year-on-year record breaking global temperatures, a new study provides a comprehensive summary of the published literature on the risks of rising heat exposure during pregnancy.

In the largest systematic review of its kind, researchers reviewed 198 studies that assessed the impact of heat on maternal, foetal, and neonatal health, across 66 countries.

The team found that for every 1°C increase in heat exposure, there was a 4 per cent increase in odds of preterm birth across all the studies. During a heatwave, the odds of preterm birth increased by 26 per cent.

Similarly, they found marked increases in other adverse outcomes such as increased risk for gestational diabetes, stillbirths, congenital anomalies and obstetric complications with increasing exposure to heat.

There is limited research on outcomes like antenatal bleeding and caesarean section risks that may be related to heat exposure and could contribute significantly to morbidity and mortality.

“Our research provides compelling evidence that heat exposure poses severe health risks for pregnant women and their babies, yet these risks are frequently underestimated,” said Prof. Matthew Chersich, executive director at Wits Planetary Health Research.

Despite a growing body of literature, research synthesising the impacts of heat exposure on maternal and neonatal health has been limited. The study aims to bridge this gap, providing insights into how heat exposure increases the risk of maternal, foetal and neonatal outcomes.

This landmark study comes as world leaders prepare for COP29, offering open-access insights that highlight the urgent need for health-focused climate policies. Wits Planetary Health Research urges stakeholders to integrate these findings into climate adaptation frameworks, with special attention to vulnerable populations in low-income countries.

“This is a pivotal moment for public health and climate action. Protecting the health of pregnant women and new borns must become a priority in our response to climate change” said Dr. Darshnika Lakhoo.

“We hope these findings will catalyse change at the policy level, ensuring at-risk populations receive the support they need.”