KIDSExtreme heat threatens pregnant women and newborns
Is this true? Make your call, then see what the science says.
Short answer: Yes. The evidence supports this.
Large reviews link hot weather in pregnancy to more preterm births and stillbirths. Health guidance lists pregnant women, babies and young children as more at risk in extreme heat. The evidence on newborns is thinner, and the studies are mostly observational.
AI-generated summary of the research cited · not reviewed by a medical professional · checked 13 October 2026 · How we checkWhat the research found
A 2025 systematic review and meta-analysis in Nature Medicine pooled 198 studies from 66 countries. Odds of preterm birth rose 1.04-fold per 1 °C of extra heat and 1.26-fold during heat waves. It also found higher risks of congenital anomalies and gestational diabetes. The stillbirth result was less certain.
A 2020 BMJ meta-analysis of 70 studies found preterm birth odds rose 1.05-fold per 1 °C and 1.16-fold during heatwaves. Stillbirths rose 1.05-fold per 1 °C. Effects were largest in women from lower socioeconomic groups and at age extremes. A 2017 review of 36 studies and a 2020 US review looked at the same outcomes.
Victorian health guidance says babies and young children, and pregnant women, are at higher risk in extreme heat. US guidance says pregnancy makes heat illness more likely. It also says raised body temperature has been linked to birth defects and other complications.
What it doesn’t mean
- Most of this research is observational. It shows heat is linked to worse outcomes, not that heat alone causes any single case. The effect on each pregnancy is small.
- The reviews mostly measured birth outcomes, such as preterm birth. Evidence on newborns and babies after birth comes mainly from general health guidance.
- If you are pregnant, make a hot-day plan with your doctor. Seek medical help straight away for signs of heat illness. Call 000 for suspected heatstroke.
Sources
General information only, not medical advice. KIDS fact-checks are generated by AI from published research and are not reviewed by doctors or other health professionals. They can be wrong or out of date. Always talk to your GP or child’s doctor about your child, and call 000 in an emergency. Spotted a problem? Tell us.
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