Climate change fuels sharp rise in extreme heat risk for pregnant people worldwide

Mumbai: Extreme heat, driven by climate change, is posing an escalating threat to maternal health and birth outcomes around the world, according to a new analysis from Climate Central, a research-based consulting and capacity building initiative that aims to bring greater focus on issues of climate change and sustainable development.

During the last five years, climate change has at least doubled the average annual number of days that are dangerously hot for pregnant people in nearly 90% of countries and territories, and 63% of cities, compared to a world without climate change, according to a press statement.

“Even a single day of extreme heat can raise the risk of serious pregnancy complications. Climate change is increasing extreme heat and stacking the odds against healthy pregnancies worldwide, especially in places where care is already hard to access. The impacts on maternal and infant health are likely to worsen if we don’t stop burning fossil fuels and urgently tackle climate change,” said Dr Kristina Dahl, Vice President for Science at Climate Central.

Climate Central analysed daily temperatures from 2020 to 2024 across 247 countries and territories and 940 cities to measure the rise in "pregnancy heat-risk days," or days when maximum temperatures exceed 95% of historic local temperatures, a threshold associated with increased risks of preterm birth.

Preterm birth can have lasting health effects on the baby and increase the risk of maternal health problems after birth.

“Extreme heat is now one of the most pressing threats to pregnant people worldwide, pushing more pregnancies into high-risk territory, especially in places already struggling with limited healthcare access. Cutting fossil fuel emissions isn’t just good for the planet — it’s a crucial step toward protecting pregnant people and newborns around the world,” said Dr Bruce Bekkar, a women’s health physician and authority on climate change’s dangers to human health.

Extreme heat is one of the most dangerous climate risks for maternal and infant health.

Research links high temperatures during pregnancy to increased risks of complications such as hypertension, gestational diabetes, hospitalisation, severe maternal morbidity, stillbirth, and preterm birth, which can lead to lifelong health impacts for children.

In most countries and territories (222 out of 247), climate change at least doubled the annual number of pregnancy heat-risk days during the last five years, across all continents, compared to a world without climate change.

In nearly one-third of countries and territories (78 out of 247), climate change added at least an extra month’s worth of pregnancy heat-risk days each year, from 2020 to 2024.

Every country analysed experienced an increase in pregnancy heat-risk days due to climate change, caused primarily by burning fossil fuels like coal, oil, and gas.

“For some countries and cities, all of the pregnancy heat-risk days experienced over the last five years were caused by climate change. In other words, in a world without climate change, these places would not have seen temperatures at or above the 95th temperature percentile during the past five years,” the press statement said.

Climate change added the highest number of pregnancy heat-risk days in developing countries that often have limited access to healthcare, including in the Caribbean, Central and South America, the Pacific Islands, Southeast Asia, and sub-Saharan Africa. These regions are among the most vulnerable to the impacts of climate change, despite contributing the least to greenhouse gas emissions.