All posts tagged: extreme heat

Surprising new study links hot days during pregnancy to fewer male births

Surprising new study links hot days during pregnancy to fewer male births

Published by Jenni Sidey

Heat does not have to reach record-breaking levels to change what happens in the womb. Across millions of births in sub-Saharan Africa and India, days with high maximum temperatures during pregnancy linked to a subtle but consistent shift in who makes it to delivery. Fewer boys were born after hotter stretches. However, the timing of the heat mattered. So did the place. The findings come from a large analysis published in the Proceedings of the National Academy of Sciences. The researchers paired high-resolution daily temperature records with about 5 million births drawn from Demographic and Health Surveys conducted from 2000 to 2022. The study’s question was blunt: can ambient temperature during conception and pregnancy nudge the human sex ratio at birth, the count of boys relative to girls? It can. But not for one single reason. Conceptual framework on biological health and behavioral mechanisms in response to temperature exposure before birth that may cause sex-specific mortality responses. (CREDIT: PNAS) A number that usually hardly moves In most countries, the sex ratio at birth falls in …

Rising Temperatures Are Taking a Toll on Sleep Health

Rising Temperatures Are Taking a Toll on Sleep Health

Published by skeptic

There’s also the physiological effect of heat itself on our breathing. “Heat may also destabilize breathing control, increase fluid retention, and promote dehydration, all of which can make the upper airway more collapsible and increase the likelihood of sleep apnea,” says Lucia Pinilla, another researcher at Flinders University investigating the subject. At the same time, sleep apnea is already expected to become a growing problem for those living in cities, due to the chronic impact of air pollution on nighttime breathing, something which is only predicted to get worse. Last year, Hong Kong researchers led a study where they found that both short and long-term exposure to PM2.5 particles—tiny airborne particles, less than 2.5 micrometers wide, which are generated by sources such as vehicle exhausts, factory emissions, and wildfires and can penetrate deep into the lungs and bloodstream—makes sleep apnea more likely. Others have shown that the same is true for nitrogen dioxide, a reddish brown gas released into the air from exhausts, power plants and other industrial facilities, while exposure to pollution also worsens …