Doctors have long known that heat puts stress on the heart, kidneys and other organs. These risks are compounded for pregnant women because the body's processes that allow you to stay cool are altered.
His the problem is that climate changecaused by burning fuels such as gasoline and coal worsens. Increasing extreme heat, high temperatures late into the night and breaking weather records means more exposure for pregnant womenespecially in developing countries.
Here's what you need to know about science pregnancy and extreme heat:
Pregnancy changes the body in a variety of ways, making it harder and more uncomfortable to dissipate heat.
“It's clear that pregnant people develop a bulge in their belly depending on how far along they are, and that's a change in their surface-to-volume ratio,” said Anna Burstein, an assistant professor at New York University Grossman School of Medicine and director of Project HEATWAVE, an initiative aimed at improving research into preventing death from extreme heat. Heat leaves your body through your skin, so as your belly gets bigger, the heat has to travel a longer distance to escape.
As pregnancy progresses, the body burns more calories, creating internal heat. The heart has to work harder, which can already be overstrained due to extreme heat. Pregnant people also need more fluids to stay hydrated, so they may become dehydrated more quickly. according to the Environmental Protection Agency.
One of the ways the body cools is by moving blood to the skin and away from the central organs, which is why a person's skin may turn red when they become hot. New research suggests that reduced blood flow to the placenta may affect fetal development.
In pregnant women dealing with potent substances such as pesticides, increased blood flow may also increase the absorption of chemicals, according to Dr. Chris Holstege, chief of the division of medical toxicology at the University of Virginia School of Medicine.
Research is beginning to show that exposure to extreme heat even months before pregnancy can affect future pregnancies, says Kara Schulte, a researcher at the University of California, Berkeley and Climate Rights International, a nonprofit that studies maternal health and heat.
During pregnancy, even short-term exposure to heat can increase the risk of serious maternal health complications such as high blood pressure blood pressure disorders during pregnancy, according to Environmental Protection Agency. This includes preeclampsia, a condition that can be fatal for both mother and child.
Heat may also get worse anxiety, depression and feelings of isolation, and after the baby is born, “all of these things are compounded by the difficulties postpartum women face in caring for their babies in the heat,” Schulte said.
As they get older, children who are exposed to extreme heat in utero may be at increased risk of experiencing developmental problems throughout their lives, potentially associated with adverse outcomes such as premature birth or low birth weight, Schulte said.
“This is an extremely understudied thing,” Burstein said, adding that much of what we know comes from studies of recruiting athletes, soldiers or able-bodied youth. “There hasn’t been the same level of commitment to women’s health research.”
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Associated Press reporter Dorani Pineda contributed to this report.
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