The escalating impacts of global warming are heightening risks for pregnant individuals, with extreme heat now being linked to severe pregnancy complications. Research highlights that rising temperatures not only contribute to heat-related illnesses but also exacerbate risks for expectant mothers and their unborn children.
Pregnant women are particularly susceptible to the adverse effects of environmental conditions and viruses. Among these, mosquito-borne diseases pose a notable threat. Viruses such as West Nile and Eastern Equine Encephalitis (EEE) are serious but relatively rare in the U.S. However, other tropical diseases like Oropouche virus disease, also known as “sloth fever,” and Zika virus can be especially hazardous for pregnant individuals.
The risk associated with these diseases is expected to grow as global temperatures rise. Climate change, driven by the excessive use of fossil fuels, is extending the mosquito season, thereby increasing exposure to these dangerous viruses.
The Association of American Medical Colleges has highlighted that extreme weather conditions, including heat, are linked to pregnancy complications, violence, and heightened exposure to pollution.
Mosquito-Borne Illnesses and Pregnancy Risks
For pregnant women, mosquito bites carry more than just inconvenience—they can result in severe infections that threaten fetal health. Although cases remain relatively rare in the U.S., the CDC acknowledges that West Nile, Zika, and Oropouche viruses all pose risks. Oropouche virus, in particular, has been associated with stillbirths and birth defects. Recent data reports over 8,000 cases globally, with some instances in Florida and New York linked to travel.
Zika virus, known for causing birth defects, has not seen local transmission in the U.S. since 2019, though significant outbreaks occurred in Latin America in 2015 and 2016.
Researchers from Climate Central found that warmer and more humid conditions, which are becoming more common due to climate change, extend the mosquito season. Their study showed that between 1979 and 2022, the number of mosquito days increased in 173 out of 242 U.S. locations. This trend heightens the risk of mosquito-borne diseases, particularly as Americans travel to areas where such diseases are more prevalent.
Heat and Pregnancy Complications
Extreme heat is linked to various pregnancy complications. The World Health Organization (WHO) reports that preterm births, the leading cause of childhood deaths, surge during heatwaves. Every 1°C increase in minimum daily temperature above 23.9°C (75°F) is associated with a 22.4% rise in infant mortality risk.
Dr. Anshu Banerjee from the WHO emphasizes the urgent need to address these issues, noting that climate change is not a distant threat but an immediate health crisis affecting vulnerable populations.
Studies indicate that high temperatures contribute to adverse birth outcomes, including preterm births and stillbirths. Additionally, elevated air pollution—worsened by heat and wildfires—further exacerbates risks such as high blood pressure, low birth weight, and developmental issues in fetuses.
Rising Risks of Miscarriages and Homicides
A 2020 review of 33 million births found significant associations between heat, air pollution, and adverse pregnancy outcomes. Studies consistently link heat exposure to preterm birth, low birth weight, and stillbirth, with some also connecting high temperatures to gestational diabetes and other complications.
Moreover, extreme weather events like hurricanes, which are becoming more frequent due to climate change, have been associated with increased fetal mortality.
Extreme heat is also correlated with higher rates of violent crime, including homicide—one of the leading causes of death for pregnant women in the U.S. Research from Harvard indicates that homicide rates among pregnant women are higher than for other pregnancy-related conditions, with firearms involved in many cases. The risk of homicide for pregnant and postpartum women increased notably during the COVID-19 pandemic.
Challenges in Accessing Care
Access to prenatal care is already a significant issue, with around 4% of women lacking health coverage at childbirth in 2021. The overturning of Roe v. Wade has further complicated access, leading to increased reports of pregnant women being denied care. Proximity to care facilities is also a problem, particularly in rural areas, where “maternity care deserts” are prevalent.
Extreme weather events can obstruct access to medical services, making travel dangerous and potentially fatal during emergencies.
Climate Change as a Women’s Health Crisis
The American College of Obstetricians and Gynecologists has termed climate change an “urgent women’s health concern” and a major public health challenge. The organization calls for comprehensive policy changes, including reducing greenhouse gas emissions and enhancing research on the impacts of climate change on women’s health.
Addressing these issues requires coordinated efforts across climate policy, healthcare infrastructure, and public health to mitigate the effects of extreme heat and other climate-related challenges on pregnant individuals and their babies.
