New York’s brutal heat is not just miserable. For people who are pregnant, it is increasingly tied to serious health problems, from preterm birth and low birthweight to life-threatening complications. As summers get hotter and stickier, researchers and clinicians say prenatal advice and workplace rules are lagging behind the new reality.
What the research shows
A 2025 scoping review led by Claire Masters and colleagues pulled together findings from more than 150 studies and found that extreme heat in both early and late pregnancy is consistently linked with higher rates of preterm birth, stillbirth and maternal complications, according to AJOG Global Reports. In a separate cohort of 403,602 pregnancies in Southern California, high exposure to extreme heat, especially in the third trimester, was associated with about a 27% higher risk of severe maternal morbidity, per JAMA Network Open.
Why pregnant bodies are vulnerable
During pregnancy, the body’s cooling system has to work overtime. Changes in thermoregulation, a big increase in blood volume and shifts in fluid balance all make it harder to get rid of excess heat, which can increase the chance that dehydration or overheating will strain the placenta and set off early labor, according to clinical guidance from MotherToBaby/NCBI Bookshelf. Those biological quirks line up with what epidemiologic studies keep finding: specific high-risk windows, especially the first month and the final weeks of pregnancy, when heat spikes appear to carry outsized danger.
Local outlook and calls for protections
Regional climate assessments project multi-degree warming for the New York City area over the coming decades, along with more dangerously hot days and more chances for pregnant residents to be hit with repeated heat exposure, according to the NYC Panel on Climate Change. Local coverage has already chronicled pregnant New Yorkers battling dizziness and other heat-related symptoms during last summer’s hottest stretches, and advocates are now pressing employers, transit agencies and clinics to expand access to cooling, paid schedule flexibility and other protections, as amNewYork reported.
What clinicians recommend
The AJOG review urges obstetricians to build heat-risk counseling into routine prenatal care, screen patients for factors that make them more vulnerable to extreme temperatures and offer clear guidance on hydration, cooling strategies and how to time outdoor or strenuous activity, according to AJOG Global Reports. Public-health experts say that kind of one-on-one advice only goes so far unless it is backed up by basic structural protections, including reliable air conditioning on public transit, guaranteed cooling breaks and workplace accommodations that keep pregnant workers out of the hottest conditions.
For pregnant New Yorkers, practical steps right now include drinking plenty of fluids, steering clear of outdoor exertion during the peak heat hours and using cooled public spaces whenever possible. Anyone who is pregnant or planning a pregnancy is urged to talk with their healthcare provider about heat-related risks and to work out precautions that fit their job, housing and daily routine.
