Rising temperatures are putting pregnant women and newborns at risk, according to a report by Climate Central.

The story was covered by Sky News and The Telegraph. 

New analysis from Climate Central, in partnership with Round Our Way, 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 and territories around the world, including heat-risk days doubling for pregnant people in the UK.

Extreme heat, driven by climate change, poses an escalating threat to pregnancy and maternal health around the world and in the UK.

The analysis shows that between 2020-2024, there was an average of 26 pregnancy heat-risk days in the UK each year — these are days with temperatures above the 95th percentile, or warmer than 95% of all temperatures observed at a given location (over the 1991-2020 period). Research shows this threshold can increase the risk of preterm birth. The analysis also shows that 13 of those 26 days were added by climate change.

The number of pregnancy heat-risk days in the UK was highest in the East of England, where 28 pregnancy heat-risk days were experienced on average each year between 2020-2024, with 16 of these (57%) being added by climate change.

This is the first analysis directly quantifying the threat to pregnant people from dangerously hot days caused by climate change. 

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, compared to a world without climate change.

The Met Office’s most recent State of the Climate report shows that 2023 was the second warmest year on record for the UK in the series from 1884, which as well as the warmest June (seen in 2023) and the September heatwave were all made more likely by climate change. It also shows that extremes of temperature in the UK have been affected much more than average temperature. The number of ‘hot’ days (28C) has more than doubled and ‘very hot’ days (30C) more than trebled for the most recent decade (2014-2023) compared to 1961-1990. 

CASE STUDIES

Amy Woolfson, who gave birth to her baby girl at Whipps Cross Hospital in London in September 2023, said:

“The thermometer that I had brought from home was recording 26.2°C by my bed at 4.28am. When the sun rose that morning, there was intense sunshine, with the windows on my side of the ward facing into the sun. At 9.30am a member of staff opened the blinds, saying the babies needed the daylight. I appreciate this would normally be the correct thing to do, but given the heat and strong sunlight I do not believe it was appropriate.

“Around 10am I took my newborn down to the ward lounge leaving a note on my bed saying I was trying to find somewhere to cool down. I said come and find me in the lounge and that I wanted to go home. I was very distressed.

“But by 12.45 the temperature had exceeded 29°C in the lounge and was 30.6°C by my bed at 1.35pm. This is completely at odds with official advice, including on hospital leaflets, that a safe sleeping temperature for babies is 16-20°C.

“I do not believe that my safety concerns were taken seriously. I do not blame any individual staff member but think this points to a management issue. I appreciate that in the short term the hospital must work with the building they have and that it’s not possible to run air conditioning around small babies,  but heat can be very dangerous for them and hot weather can generally be forecast”. I feel that I was feel as a difficult patient rather than someone raising a genuine safety concern and that my discharge was rushed as a result.

“Nobody seemed to recognise that the heat and strong sunlight were a potential safety issue, and nobody appeared to be monitoring the temperature. I was left with the impression that there was no plan for dealing with hot weather. Later, when I learned that when a ward or clinical area is over 26°C that it should be treated as an overheating incident, triggering a risk assessment and reported to NHS England, I put in a formal complaint to the hospital. 

“The Trust’s first reply said that in hot weather it is not possible to keep the maternity ward temperature below 26°C. The outside temperature in September 2023 was in the low 30s, so this got me thinking whether an incident was reported in respect of the 2022 heatwave, when London temperatures exceeded 40°C” but NHS estates data for 2022/23 showed that Barts Health NHS Trust - of which Whipps Cross Hospital is a part - recorded zero overheating incident. Later the Trust told me that it does not have a formal method of recording and reporting overheating incidents. It is ridiculous that the Trust is legally required to report these things but there is no way of collecting the data.

“There are important steps to be taken to make maternity wards safer like monitoring the temperature in all patient areas, providing a cool area during hot weather and giving advice about staying cool and hydrated. Is the NHS really thinking about the climate side of things.”

Sofie Jenkinson, Co-Director of Round Our Way, an organisation that supports people impacted by climate change in the UK, said:

“Daily we see more examples of the ways climate change is impacting our lives, from the cost of essential  food items to football games being cancelled to the impacts of storms, floods and heatwaves. This new analysis shows the impact warmer weather is having on people we love – in this case, pregnant women. Extreme heat while pregnant can have very serious consequences for both the pregnant person themselves and their child. We need to see more support for those on the sharp end of climate impacts in the UK and further political action to tackle  the causes such as emissions, to ensure we don’t see things getting worse in our communities and at our doorstep.”

Meteorologist, Gemma Plumb, UK Weather and Climate Lead at Weather Change said:

“Climate change is making our weather more extreme, and we are seeing extreme heat becoming more frequent and intense, including here in the UK. In fact in 2022, the UK saw temperatures reach 40C for the first time on record. Now extreme heat is associated with significant health impacts, and this includes presenting a severe threat to maternal health and birth outcomes.”

Dr. Bruce Bekkar, a women’s health physician and authority on climate change’s dangers to human health said:

“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,”

Dr. Kristina Dahl, VP for Science at Climate Central, said:

“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.”