If you're expecting during the heat of summer, you don't need anyone telling you how uncomfortable and sometimes unbearable it can be. Attempting to maneuver your growing pregnant belly around in the high temps and humidity, searching the clothing racks for maternity wear that's breathable (and ideally sweat-wicking) and battling swollen everything, from your feet to your fingers, is no easy feat.
But a new study might give you extra incentive to stay plopped on the couch with the AC fanning your face. Research published in the Journal of Environmental Research and Public Health found that exposure to extremely hot temperatures linked to climate change can negatively impact both pregnant moms and their babies. According to researcher, Sabrina McCormick, Associate Professor at Milken Institute School of Public Health at the George Washington University, pregnant women are an integral group of the global climate conversation "whose unique vulnerabilities to heat need to be factored into public policy."
The researchers based their conclusion off what they're calling the most extensive systematic review of studies that identify the various ways heat-related exposures put pregnant women and developing fetuses at risk for adverse health effects. The various studies point to impacts such as birth outcomes, including changes whether a baby is born full-term or born early, birth weight, still birth as well as neonatal stress, or the stress experienced by a newborn baby.
"Hot weather can make us all uncomfortable, but it is particularly hard on pregnant women," says Jaime Knopman, MD, board-certified reproductive endocrinologist and co founder of Truly-MD.com. "When you are pregnant, your blood volume changes, and this shift in fluids can lead to lightheadedness, fainting and even early labor." Add heat to this combination and a mom-to-be can find herself in a potentially dangerous situation.
Knopman also notes that dehydration can be a factor that in causing early contractions, which can lead to early labor. Additionally, the fetus is surrounded by water (the amniotic fluid), so there is more than one reason to stay hydrated throughout pregnancy, regardless of the season or temperature outside.
While this research is certainly informative, and a reminder to stay out of the extreme heat during pregnancy, it's no cause for alarm—yet. "The key word here is 'too' hot," says Linda Green, MD, South Florida-based OB/GYN. "As long as women use common sense—stay hydrated when out in the heat so their blood pressure can be maintained and do not allow themselves to become lightheaded and overheated—they should be fine and so should the baby."