The Impact of Heatwave Exposure and Climate Change on Maternal Health and Pregnancy Outcomes: A Public Health Review
DOI:
https://doi.org/10.69855/mgj.v3i3.887Keywords:
Climate Change, Heatwave, Extreme Heat, Maternal Health, Pregnancy Outcomes, Preterm Birth, Public HealthAbstract
Background: Climate change is increasing the frequency, intensity, and duration of extreme heat events. Pregnancy is a heat-vulnerable physiological state because maternal cardiovascular, metabolic, and thermoregulatory demands rise while fetal development depends on stable uteroplacental function. Purpose: This review synthesizes evidence on heatwave exposure, maternal health, pregnancy outcomes, biological pathways, vulnerable populations, and public-health responses. Methods: A narrative public-health review was conducted using peer-reviewed systematic reviews, meta-analyses, cohort studies, and authoritative guidance, with emphasis on evidence published from 2020 to 2025 while retaining selected earlier landmark studies. Results: The strongest and most consistent evidence concerns preterm birth. A 2025 meta-analysis of 198 studies from 66 countries reported higher odds of preterm birth with increasing heat exposure and during heatwaves. Evidence also links heat with low birth weight, stillbirth, gestational diabetes, hypertensive disorders, placental complications, and selected congenital anomalies, although effect sizes and certainty vary by outcome. Proposed pathways include dehydration, cardiovascular strain, altered uteroplacental perfusion, inflammation, oxidative stress, endocrine responses, and placental dysfunction. Social disadvantage, outdoor work, poor housing, and limited access to cooling may amplify risk. Conclusion: Extreme heat should be incorporated into maternal-health surveillance, antenatal counselling, occupational protection, heat-health warning systems, and climate-resilient health services, especially in tropical and resource-constrained settings.
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