Extreme heat is already increasing health risks for pregnant women and new-borns, with nearly three-quarters of maternal healthcare professionals across five countries reporting a rise in heat-related cases and complications over the past five years, according to a new international survey.
The survey, commissioned by global health foundation Wellcome, covered 1,000 healthcare professionals in India, Australia, Brazil, the United Kingdom and Zimbabwe. Around 73 per cent of maternal healthcare respondents said they had seen an increase in heat-related cases or complications affecting pregnant women, while 76 per cent reported an increase in cases affecting foetal or new-born health.
Nearly all those surveyed said they had personally cared for a pregnant woman or baby whose health they believed had been adversely affected by extreme heat. This included 98 per cent who had treated pregnant women and 99 per cent who had cared for babies.
The findings were released on October 5, 2026, first day of the official pre-COP ministerial meeting in Fiji, ahead of the 31st Conference of Parties to the United Nations Framework Convention on Climate Change (COP31), scheduled for November 9-20. The survey was conducted online between September 17 and October 1, 2026, with 200 maternal healthcare professionals surveyed in each of the five countries.
The findings come at a time when 33 countries this recorded their hottest July, underscoring the growing threat extreme heat poses to health systems and communities worldwide.
The survey also comes amid growing scientific evidence linking heat exposure during pregnancy with adverse outcomes including preterm birth, low birth weight, stillbirth and maternal complications.
Research cited by Wellcome found that for every 1 degree Celsius rise in heat exposure, the odds of preterm birth increase by around 5 per cent, while exposure to heatwaves was associated with a 25 per cent higher risk of obstetric complications.
Healthcare professionals surveyed by Wellcome also reported seeing specific problems they associated with extreme heat. Around 23 per cent said they had encountered pregnancy complications requiring additional monitoring or treatment, while 34 per cent reported cases of low birth weight or restricted growth.
Another 36 per cent said they had seen dehydration and heat-related illness among new-borns, while 33 per cent reported difficulties involving feeding, breathing and temperature regulation.
Extreme heat was also affecting access to healthcare. More than a quarter of respondents, or 27 per cent, said high temperatures were making it harder for pregnant women and families to travel to or access care, while 29 per cent reported an increase in urgent or emergency presentations.
But even more worrying was that healthcare workers expect the problem to worsen. Around 81 per cent of those surveyed said they were concerned that extreme heat would pose a growing threat to maternal, foetal and new-born health over the next five years unless further action was taken.
“Extreme heat, fuelled by climate change is impacting our way of life and our health — and yet many countries are not prepared. With El Niño pushing temperatures higher, the failure to act is costing lives,” said Madeleine Thomson, head of climate impacts and adaptation at Wellcome. She added that measures such as early warning systems and cooler buildings were already available but often failed to reach those most at risk.
Meanwhile, UN Climate Change Executive Secretary Simon Stiell, speaking at an event on maternal health and global heating on October 5, described pregnancy and birth as an emerging “faultline” in the climate crisis.
“The picture is clear and very disturbing: as extreme heat worsens, pregnancy and birth are now a new faultline in the global climate crisis, and one which is potentially fatal,” Stiell said.
He warned that the risks would fall disproportionately on those already facing limited access to healthcare, safe housing, cooling, water and electricity.
“‘Staying cool’ is simply not an option when there is no cool place to go,” he said.
Ahead of COP31, Wellcome is calling for pregnant women, new mothers and babies to be explicitly included in national climate and health plans, with funded and accountable measures to protect them from heat.
It has also called for the development of the first World Health Organization clinical guidance on heat, pregnancy and the postpartum period, as well as stronger data and surveillance systems that integrate heat exposure into maternal and new-born health monitoring.