Extreme heat is making pregnancy and childbirth more dangerous, according to health experts, who warn that rising temperatures are taking a silent toll on mothers and newborns. A new survey commissioned by the global health foundation Wellcome found that 73 per cent of maternal healthcare workers have seen heat-related cases or complications increase over the past five years.
Simon Stiell, head of the UN's climate body, highlighted the findings on 5 October at the pre-COP summit in Nadi, Fiji. He stressed that the dangers of extreme heat go beyond the obvious health impacts, pointing to links with premature birth, stillbirth, low birth weight, and complications for mothers. According to Wellcome, every 1°C rise in temperature is associated with a five per cent increase in premature births and a seven per cent increase in gestational diabetes.
But Stiell argues that many of these risks can be mitigated through better planning, from improved heat alerts to ensuring clinics have reliable water and electricity. The survey, which polled 1,000 maternal health professionals in Australia, Brazil, India, the UK, and Zimbabwe, found that 98 per cent had cared for a pregnant woman whose health they believed was affected by extreme heat, and 99 per cent said the same for a baby.
Health workers call for more support
The vast majority of those surveyed said they need more help: 92 per cent called for additional training, guidance, and resources to protect pregnant women from heat. Stiell delivered his speech at a Wellcome-organised event on the opening day of pre-COP, which runs from 5 to 8 October. The meeting is the final major gathering before COP31, scheduled for 9–20 November in Antalya, Türkiye.
This year's co-hosts, Türkiye and Australia, have billed the summit as an “Implementation COP” focused on turning pledges into progress. Their priorities include climate finance, resilient cities and infrastructure, and protecting vulnerable regions. However, both countries have faced criticism for their continued embrace of coal, often described as the dirtiest form of energy.
Stiell argued that governments should make maternal and newborn health a central part of climate action. Pregnant women who work outdoors, lack adequate cooling at home, or must travel long distances for medical care may have little protection during extreme heat. Clinics themselves can struggle when water, electricity, or cooling systems fail.
“Staying cool is simply not an option when there is no cool place to go,” Stiell said.
Practical solutions already exist
In his call to action, Stiell urged governments to invest in practical measures such as heat alerts, better-trained healthcare workers, water and electricity infrastructure, and clinics better prepared for extreme temperatures. Around the world, some of these ideas are already being tested.
In Zimbabwe and South Africa, a Wellcome-funded project involving 1,600 women is testing low-cost protections against extreme heat, including sunhats, water bottles, umbrellas, and fans. Some communities are also painting roofs white, broadcasting heat advice on the radio, and training health workers to send daily warnings via an app.
Cities can also reduce the heat that pregnant women and children face in their daily lives. Some of the most promising fixes are relatively cheap and can make use of existing infrastructure. For example, researchers at the University of Manchester found that rooftop rainwater systems could help keep cities cool by spraying stored rainwater onto hot roofs. As the water evaporates, it cools the roof, reducing the amount of heat entering the building and the need for air conditioning—which in turn reduces the heat expelled outdoors.
In Spain, hundreds of public buildings have been designated as climate shelters, offering people a cool refuge during dangerous heatwaves. Barcelona alone has around 400 such shelters, including libraries, museums, and municipal markets.
The COP31 host city is already searching for solutions. Antalya has mapped neighbourhoods where high temperatures and vulnerable populations overlap, then used the data to direct shade, green space, early-warning systems, and health support towards those areas.
Paying for measures that safeguard society's most vulnerable will be another test for governments. At COP30, nations agreed to triple climate adaptation financing by 2035. COP31 will test whether those promises translate into real action. As Stiell put it: “A changing climate must never be accepted as a reason pregnancy and birth become less safe. A newborn's healthy start must never depend on a family's ability to escape the heat.”
