Pregnant this summer in Houston? Texas heat poses a special danger

Pregnancy brings significant changes to the body, the most intense of which is the increased workload placed on the cardiovascular system. These changes lead to an increase in blood volume, heart rate and internal temperature.

As the outside temperature rises, the risks of almost all pregnancy-related complications seem to increase. These complications include preterm labor, preterm delivery, low birth weight, gestational hypertension, gestational diabetes, and emergency room visits.

Several factors contribute to heat stress during pregnancy, such as increased fat deposition, body mass, and body heat production due to the metabolic activity of the child and the surrounding placenta.

“The baby typically maintains a body temperature about half a degree higher than the mother’s, which allows the baby to release excess body heat into the mother’s body,” Hart said. “However, when the mother’s core temperature rises, any extra heat energy will stay with the baby, potentially increasing the risk of complications.”

According to the American Heart Association, excessive heat exposure during pregnancy can lead to dehydration, reduced blood flow to the placenta, or trigger an inflammatory response that can lead to premature delivery.

Dehydration can increase Braxton Hicks contractions, also called “entrainment” or “false” contractions. Hart said if you notice more of these contractions after being outside in the heat, try moving to a cooler environment, drink plenty of fluids containing electrolytes and get some rest. If symptoms do not improve, it is best to contact your doctor.

As part of its normal heat management process, the body sends blood to the skin and dilates pores to trigger sweating. However, according to Hart, if a significant amount of blood flow is diverted to the skin, it can reduce the amount of blood available to the placenta.

Excessive heat can cause oxidative stress, which occurs when the body has an excessive amount of harmful molecules called free radicals, and not enough antioxidants to neutralize them. Hart said this leads to an inflammatory response that can trigger preterm labor by affecting the interaction between the mother’s and child’s circulatory systems.

It’s hard to completely avoid the heat in the summer, but Hart suggests some simple heat safety measures you can take: