Climate Change Fuels Sharp Rise In Extreme Heat Risk For Pregnant Women

New analysis finds climate change poses a severe threat to maternal health and birth outcomes, doubling the number of days that are dangerously hot for pregnant people in 90% of countries around the world.

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. In 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.

Climate Central analyzed 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.

This is the first analysis directly quantifying how climate change is increasing dangerously hot days for pregnant people.

Key findings include:

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

● 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.

● 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.

● 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.

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, hospitalization, severe maternal morbidity, stillbirth, and
preterm birth, which can lead to lifelong health impacts for children.

“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.

“Even a single day of extreme heat can raise the risk of serious pregnancy complications,” said Dr. Kristina Dahl, VP for Science at Climate Central. “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.”

This analysis quantifies how climate change is influencing the frequency of extreme heat associated with increased risks of preterm birth and examines where pregnant people are most at risk, using two primary mechanisms:

● Pregnancy heat-risk days: We counted the number of days with temperatures warmer than 95% of temperatures observed at a given location — a threshold associated with an increased risk of preterm birth. We define these extremely hot days as “pregnancy heat-risk days.”

● The Climate Shift Index (CSI) system: We calculated the number of pregnancy heat-risk days that would have occurred in a world without human-caused climate change (i.e., a counterfactual scenario) and compared that to the total number observed each year. This allowed us to count how many pregnancy heat-risk days were added by climate change annually.

The report link : http://www.climatecentral.org/report/pregnancy-heat-risks