Pakistan’s searing heat is putting unborn babies at serious risk, with new research showing pregnant women in the country’s hottest regions face up to 70 per cent greater odds of delivering a dangerously small infant.
The findings come from a major collaborative study published in the journalย BMC Medicine, which tracked health data from more than 85,000 mothers and babies across Pakistan between 2008 and 2017. Researchers matched birth outcomes to monthly temperature records to measure how heat affects infant size before birth.
What the Numbers Show
Nearly one in five babies in the study, 18.7 per cent, was born with low birth weight, defined as weighing less than 2.5 kilograms or being described as smaller than average at birth. Researchers estimated that roughly 11.26 million babies born in Pakistan during the study decade had low birth weight.
Critically, up to 13 per cent of those cases were directly linked to hot weather conditions. That translates to approximately 1.24 million heat-related low-birth-weight cases over a single decade, a figure researchers warn will climb sharply as global temperatures rise.
“Pregnant women in Pakistan face a heightened risk of delivering infants of low birth weight following exposure to extreme temperatures, with percent excess risk varying among provinces from approximately 30 per cent to 70 per cent at high percentiles,” the study’s authors wrote.
Regions Hardest Hit
Not all of Pakistan faces equal danger. Districts in southern Punjab, northern Baluchistan, and Sindh showed the highest vulnerability, driven by a combination of extreme heat, poverty, and poor air quality.
“That risk was up to 70 per cent higher in some areas of Pakistan, which are more susceptible to adverse birth outcomes due to their hotter climate and greater socioeconomic disadvantage, among other factors,” said Associate Professor Zohra Lassi, the project lead from the University of Adelaide’s Robinson Research Institute.
Gilgit-Baltistan, situated in Pakistan’s mountainous north, was the only region where cold, rather than heat, was associated with low birth weight, a finding researchers attributed to its extreme altitude, harsh winters, and limited healthcare access.
Poverty and Pollution Make It Worse
The study found that heat does not act alone. Women from the poorest households faced the steepest risk, with relative risk estimates nearly three times higher than average during extreme heat events. Women with little or no education also showed greater vulnerability.
“In Pakistan, heat does not occur in isolation. It interacts with existing challenges such as poverty, limited healthcare access, poor air quality, and maternal undernutrition, which means climate change can deepen risks for mothers and newborns in ways that are far from equal,” said lead author Hira Fatima, a Postdoctoral Research Fellow at the HEAL Global Research Centre at the University of Canberra.
Air pollution compounded the problem further. Women exposed to hazardous levels of fine particulate matter faced more than double the heat-related risk of delivering a low-birth-weight baby compared to women in cleaner environments.
What Comes Next
Under high-emission climate scenarios, the share of low-birth-weight cases attributable to heat is projected to increase by 8 to 10 per cent by the 2060s. In Sindh alone, the heat-attributable burden is expected to rise from 8 per cent to more than 18 per cent.
“Low birth weight is already a major neonatal health issue in Pakistan, leading to neonatal mortality and impaired long-term health problems such as stunted growth or cognitive defects,” said Associate Professor Lassi.
Fatima stressed that warnings alone are insufficient. “Climate adaptation in Pakistan cannot stop at heat warnings alone. It needs to include stronger maternal health services, better protection for vulnerable pregnant women, and targeted support for the districts facing the greatest heat risk.”
Lassi echoed that call: “Interventions designed to mitigate the effects of climate change, enhance access to essential healthcare services, and promote sustainable development are urgently required. This includes public health programs to educate and help pregnant women cope with extreme heat events, along with much-needed investment in improvements to health infrastructure.”
Support Us To Sustain Independent Environmental Journalism In India.
Keep Reading
Highway Halt Puts Kashmirโs Fruit Economy at Risk
Railway line expansion plan put Kashmirโs apple orchards at risk
Warmer winters in Kashmir raise concerns over apple and crop yields
Stay Connected With Ground Report For Underreported Environmental Stories.
