A new assessment of the April 2024 heatwave shows that climate change is no longer only an infrastructure, water or livelihood crisis. It is also entering the most private spaces of urban life: pregnancy, childbirth and newborn care. Across India, Bangladesh and the Philippines, the heat during that month was associated with an estimated 16,150 additional premature births, including 10,600 linked specifically to human-caused global warming. India accounted for 8,830 of those climate-linked cases, according to a study by Zero Carbon Analytics cited in the report.
The finding matters because it shifts the climate-health discussion from broad exposure to a specific pressure on health systems. Heatwaves are generally measured through temperature records, excess deaths, electricity demand or water stress. The study instead connects an extreme heat event to premature births, a health outcome that can impose long-term costs on families, hospitals and public services. It also shows why heat action plans cannot be treated only as emergency arrangements for outdoor workers, older people or people with existing illnesses.
The April 2024 event was unusual in both scale and attribution. Across the three countries, premature births were estimated to be 3.6 per cent higher in India, 11.9 per cent higher in Bangladesh and 10 per cent higher in the Philippines than during a normal April. The report distinguishes between all additional premature births during the heat and the smaller number attributed specifically to human-caused warming. In India, the latter figure was estimated at 8,830; Bangladesh accounted for 1,479 and the Philippines for 263.
That distinction is important for interpreting the evidence. The 16,150 figure describes the estimated increase during an unusually hot month compared with a normal April. The 10,600 figure describes the estimated portion that would not have occurred in a world without human-caused temperature rise. The numbers are therefore not interchangeable, but together they indicate how climate change can amplify an existing health risk.
The study also found that the heat event in South Asia became approximately 45 times more likely because of human-caused climate change. In the Philippines, researchers assessed that a comparable event would have been almost impossible without that influence. These findings do not mean that every premature birth during the month was caused by heat or climate change. They indicate a population-level association between the intensity of the heat event and an increase in premature births, with a defined share attributed to human-driven warming.
The geography of the burden is equally significant for India. Bihar, Uttar Pradesh, West Bengal and Jharkhand were estimated to account for approximately two-thirds of the country’s additional premature births during the event. These states combine large populations with substantial demand for maternal and newborn health services. The concentration means that a national climate-health response cannot rely only on broad advisories issued from central or state capitals. It must reach pregnant women, frontline health workers, primary health centres, maternity hospitals and local administrations in the districts where exposure and service pressure overlap.
The report does not provide a complete district-level assessment of hospital capacity, access to cooling or the socio-economic profile of affected mothers. That limits what can be concluded about the precise pathways from heat exposure to premature birth. However, the distribution of estimated cases identifies where more detailed surveillance is needed. It also underlines the importance of connecting climate information with routine maternal health data rather than treating the two systems as separate administrative concerns.
The medical risk associated with premature birth extends beyond delivery. Premature babies face a higher likelihood of serious health problems in the early stages of life, and the report notes possible effects on physical growth, brain and nervous-system development, and later social and economic outcomes. For families, this can mean longer hospital stays, higher care requirements and prolonged uncertainty. For the public health system, it can mean additional demand for neonatal care, trained staff, equipment and follow-up services.
Dr Rashmi Agrawalla, associate professor in Community and Family Medicine and climate-change nodal officer at AIIMS Guwahati, said pregnant women in climate-vulnerable countries such as India are directly exposed to these risks. She identified anaemia, poor nutrition and prolonged outdoor work as factors that can intensify heat-related risks during pregnancy. Her comments point to an important institutional issue: exposure is not determined by temperature alone. It is shaped by housing conditions, work, nutrition, access to water, the ability to rest and the distance to medical care.
This is where the urban dimension becomes visible even when the most affected locations are not limited to large metropolitan areas. Heat is experienced through homes, workplaces, roads, public transport, hospitals and neighbourhood services. Pregnant women living in dense settlements or poorly ventilated housing may have limited access to indoor cooling. Those working outdoors or in informal employment may not be able to change their hours or stop work during the hottest part of the day. A heat warning has limited value if people cannot act on it without losing income, care access or mobility.
The study’s projections for 2050 make the issue more consequential. Using two climate scenarios, it estimated that India could experience more than 15,000 additional premature births during a normal April by the middle of the century. In this projection, a normal April around 2050 could carry a greater premature-birth burden than the exceptionally hot April of 2024. Uttar Pradesh was projected to face the largest impact, followed by Bihar and Rajasthan. For Bangladesh, the report estimated approximately 1,500 additional premature births during a normal April by mid-century, with the Dhaka division most affected, followed by Chattogram and Rajshahi.
These projections should be read as estimates under specified temperature scenarios, not as a fixed forecast. Their policy value lies in showing how an extreme event can become part of ordinary seasonal conditions as the baseline temperature rises. The central planning challenge is therefore not only how to respond to exceptional heat, but how to redesign routine maternal and neonatal services for a hotter climate.
The report says that existing maternal-health policies and heat-action plans in India, Bangladesh and the Philippines do not yet systematically include protections for pregnant women and newborns. That gap concerns both policy design and implementation. Health advisories for pregnant women, access to cooling, early-warning systems and heat-sensitive antenatal care would need to be integrated into local service delivery. Hospitals and primary health facilities would also need protocols for identifying heat stress and maintaining safe conditions during prolonged hot periods.
Such integration requires coordination between departments that often work on separate timelines. Meteorological agencies issue forecasts and warnings; health departments manage antenatal and neonatal services; municipal bodies influence water supply, public spaces, housing conditions and local cooling facilities; labour authorities address workplace exposure; and community health workers maintain contact with households. Without a clear institutional chain linking a heat alert to specific action for pregnant women, the warning may remain informational rather than protective.
Dr Joanne Bentley-McCune, the study’s lead author and a senior research analyst at Zero Carbon Analytics, said rising temperatures were making extreme heat events more frequent and intense and increasing the risk of premature birth. She pointed to improved antenatal care, access to cooling and timely warning systems as measures that could reduce some risks, while also stating that these actions cannot eliminate the full burden created by climate change. The report therefore places adaptation and emissions reduction in the same frame: health systems must prepare for heat already occurring, while governments also limit the warming that increases future exposure.
The wider international response is beginning to recognise this connection. The report refers to a global framework launched by the World Health Organization, the World Meteorological Organization, UNICEF and the United Nations Population Fund to track extreme-heat risks for pregnant women, newborns and children. It also notes that health is expected to receive attention at the upcoming COP31 climate conference and that the United Nations climate leadership has called for action on heat-related impacts during pregnancy and childbirth.
For Indian cities and states, the immediate evidence is not a case for attributing every adverse birth outcome to climate change. It is a case for improving the way risk is recorded and managed. Maternal-health data, heat exposure, occupational conditions, nutrition and access to cooling need to be considered together if authorities are to identify vulnerable groups and allocate services effectively. The estimated concentration of cases in Uttar Pradesh, Bihar, West Bengal and Jharkhand provides a starting point for that work, but the supplied study does not establish how the burden varies between urban and rural areas or between different income groups.
What the evidence confirms is narrower but important: the April 2024 heat event coincided with a measurable increase in estimated premature births across three Asian countries, and a substantial share of that increase was attributed to human-caused warming. What remains to be established through further surveillance is how heat exposure operates across different communities and which interventions reduce the risk most effectively. The developments to monitor are the incorporation of pregnancy and newborn protections into heat-action plans, the availability of local cooling and warning systems, and whether maternal-health programmes begin treating extreme heat as a routine climate-related risk rather than an occasional emergency.
