A groundbreaking study conducted by the University of Sydney is set to examine the risks associated with heat exposure during pregnancy. Pregnant women across the globe often find themselves exposed to extreme heat while performing daily tasks, and this study aims to shed light on the potential dangers it poses to both expectant mothers and their unborn children.
The study, funded by a £2 million grant from the Wellcome Trust, is part of a broader initiative dedicated to understanding why heat can be a significant risk factor during pregnancy. Researchers have already identified numerous adverse outcomes associated with heat exposure during pregnancy, including preterm birth, low birth weight, stillbirth, and congenital anomalies.
Alarmingly, preterm birth, in particular, has seen a 16% increase during heatwaves, making it a pressing global concern. In fact, prematurity already ranks as the leading cause of death for children under the age of 5. Although heat’s detrimental effects on pregnancy are well-established, there is still much that remains unknown. This knowledge gap is what inspired the researchers at the University of Sydney to conduct their groundbreaking study using a climate chamber.
The study’s objective is to replicate the experiences of pregnant women exposed to extreme heat while engaging in physical activities. The climate chamber, heated to 36°C with humidity levels reaching 56%, mimics the challenging conditions many pregnant individuals face daily. The study will involve dozens of pregnant women who will cycle in the climate chamber, gathering invaluable data on their physiological responses to heat stress during different stages of pregnancy.
The Sydney team will collaborate with researchers in India and Bangladesh who are conducting a complementary study using temperature sensors worn by pregnant women. Together, these studies will help create a unique model to establish safe heat exposure limits during pregnancy. Maintaining a safe core temperature is essential during pregnancy to avoid complications, and sweating is the body’s primary cooling mechanism.
However, much of the existing research on heat stress has focused on male subjects, which has led to limitations in understanding how pregnancy affects thermoregulation. Pregnant individuals face unique challenges as their body mass increases, and their skin surface area for heat dissipation decreases.
Pregnant women do have some mechanisms to aid in temperature regulation, such as increased plasma volume and dilated skin vessels. However, the exact mechanisms and safe limits for heat exposure during pregnancy remain uncertain. The study at the University of Sydney aims to provide much-needed clarity on these issues and develop a practical tool that can help pregnant individuals make informed decisions about heat exposure.
In addition to the physiological risks, extreme heat exposure can indirectly impact pregnant women’s health. Women in regions with high temperatures, such as rural areas in Kenya, often engage in physically demanding tasks outdoors, which can lead to various health problems, including high blood pressure, miscarriages, or premature births.
While there are concerns about the participation and safety of pregnant women in this type of study, the researchers are committed to prioritizing safety. The study will closely monitor participants, allowing them to withdraw at any time and ensuring that their core temperatures remain within safe limits.
This pioneering research represents a significant step toward understanding the effects of heat exposure on pregnant individuals and their babies. By providing concrete guidance on safe heat exposure limits during pregnancy, the study aims to protect the health and well-being of expectant mothers in a warming world.
Journal Reference
(N.d.). Retrieved from https://www.science.org/content/article/how-much-heat-dangerous-during-pregnancy
