Nearly three in four maternal health workers in Australia, Brazil, India, the UK and Zimbabwe say heat-linked pregnancy complications have increased over five years. Midwives and researchers are already testing simple ways to keep pregnant women cool.
Zimbabwe’s maternal health workers reported the largest rise in heat-linked pregnancy problems of any country in a five-nation poll. There, 85% said heat-related cases or complications had increased over the past five years. Australia followed at 79%, then Brazil at 74%, the UK at 66% and India at 62%, Inter Press Service reports.
Wellcome, the global health foundation, commissioned the poll of 1,000 health professionals from the polling company Censuswide in September 2026. Across all five countries, 73% reported more heat-related cases or complications affecting pregnant women. For complications affecting babies before or after birth, the figure was 76%.
What midwives and doctors are seeing
Almost all respondents (98%) said they had cared for a pregnant woman they believed was harmed by extreme heat. Some 23% had seen hypertensive disorders, including pre-eclampsia, which they linked to heat. Nearly 18% reported pregnancy loss or stillbirth they believed heat had contributed to, and 19% reported preterm contractions, labour or birth.
The respondents were midwives, obstetricians, gynaecologists, doctors and nurses. The survey records their professional judgement and did not try to prove that heat alone caused any individual complication, IPS reports. It is a perception poll and has not been peer reviewed.
A systematic review published in Nature Medicine in November 2024 pooled 198 studies from 66 countries. Each 1°C rise in heat exposure was linked to a 4% increase in the odds of preterm birth. During heatwaves, the odds of preterm birth rose by 26%.
An earlier review in the BMJ in 2020 analysed 70 studies in 27 countries. It linked each 1°C rise to 5% higher odds of stillbirth, according to an August 2026 summary in American Family Physician. Both reviews drew on observational studies, which show associations and can’t prove cause.
A quarter of respondents (26%) said limited awareness of heat risks held women back from protecting themselves. Another 24% cited the need to work outdoors or in hot conditions. Some 23% pointed to limited access to cooling, and the same share to the cost of electricity, water or protection. Nearly a quarter (24%) also reported interruptions to electricity, water, cooling or equipment, IPS reports.
Fans, cool rooms and heat alerts
The US Centers for Disease Control and Prevention (CDC) has clinical guidance on heat and pregnancy that sets out practical steps. It says “even a few hours in a cool location can lower the health risk from heat.” It advises regular drinks and food through the day, loose light-coloured clothing, and outdoor tasks at the coolest time of day. Above about 32°C (90°F), it notes, a fan can raise body temperature.
The CDC lists heavy sweating, muscle cramps, weakness, headache, nausea and preterm contractions among signs of heat-related illness. Pregnant women who notice these signs can ask a midwife or doctor for help.
The International Confederation of Midwives (ICM) describes clinics in Zimbabwe painting roofs to cut indoor temperatures and moving maternity services to cooler parts of buildings. ICM also points to the MotherHeat Alert app, which warns pregnant and postpartum women and maternity staff about rising temperatures.
Wellcome says it is investing more than £20 million in local research, including the HAPI study in Zimbabwe and South Africa. The study follows 1,600 women in rural Mount Darwin and urban Tshwane. It is testing handheld fans, reflective roof paint for health facilities and community-led climate information, Climate Home News reports.
A call before COP31
Some 92% of respondents wanted more training and resources. Another 82% said leaders should make protecting pregnant women and babies from heat a higher priority. Wellcome released the findings in Fiji at a pre-COP ministerial meeting. Simon Stiell, executive secretary of UN Climate Change, said: “Harm that is not counted is too easily ignored.”
Julia Gillard, chair of Wellcome, said “pregnant women must not be invisible.” Wellcome is urging governments to include pregnant women and babies in their national climate and health plans. Ministers next meet at the COP31 summit in Antalya, Türkiye, in November.
This article is for information only and does not replace advice from a qualified health professional.
Header image: Jawn Gangte on Unsplash