Extreme heat, driven by climate change, poses an increasing threat to maternal health and birth outcomes in India and other developing countries due to limited access to healthcare, according to a new analysis by Climate Central, a US-based climate research organisation.
The analysis found that India recorded an average of six additional days of dangerously high temperatures for pregnant women each year over the last five years. Among the states, the number of "pregnancy heat-risk days" was highest in Goa, Kerala, Sikkim and Assam compared to others between 2020 and 2024.
The term "pregnancy heat-risk days" refers to extremely hot days that are associated with heightened risks of preterm birth (birth before 37 completed weeks of gestation) and complications in maternal health. Preterm birth can have lasting health effects on the baby and increase the risk of maternal health problems after birth.
The analysis by Climate Central, an independent group of scientists and communicators, is based on a counterfactual scenario – a world without human-caused climate change and compared that to the total number observed each year.
The study shows that heat exposure during pregnancy is linked to higher risks of complications like hypertension, gestational diabetes, maternal hospitalisations and severe maternal morbidity. Further, it is associated with an increased risk of adverse outcomes such as stillbirth and preterm birth.
Burning fossil fuels such as coal, oil and gas primarily causes climate change.
Between 2020 and 2024, India experienced an average of six additional pregnancy heat-risk days each year. The typical annual number of dangerous heat for pregnant women in India reached 19 days, with climate change accounting for one-third of this increase (i.e., six additional days).
Data shows that India’s traditionally smaller and Himalayan states recorded more dangerous heat days for pregnant women than bigger and mainland states. At 32 days, Sikkim reported the highest number of pregnancy heat-risk days attributed to climate change. Goa and Kerala followed with 24 and 18 additional days, respectively.
Among the bigger and more populated states, Assam and Uttarakhand are at the top. The average annual dangerous heat days added by climate change are 22 days and 12 days, respectively.
However, densely populated states like Uttar Pradesh, Bihar, Delhi, Haryana, Punjab, Jharkhand, and West Bengal registered negative impact days. The study could not explain why.
Other bigger states like Maharashtra, Madhya Pradesh, Karnataka and Tamil Nadu, added dangerous heat days for pregnant women in the range of 4-8 days.
At the city level, Panjim, Thiruvananthapuram and Guwahati recorded over 90% additional pregnancy heat-risk days due to climate change. Panjim topped the list with 39 days, followed by Thiruvananthapuram with 36 days and Guwahati with 21 days. Smaller cities mostly in the Northeast region and in Union Territories like Daman and Port Blair recorded higher number of days compared to mainland cities.
Among larger cities, Mumbai reported 17 and Vasai-Virar 21 additional pregnancy heat-risk days related to climate change from 2020 to 2024. Chennai and Bengaluru (3 days), Indore and Jaipur (7 days) and Pune (8 days) recorded additional pregnancy heat-risk days during the same period.