Air Date: Week of October 23, 2026

Research suggests a link between ultrafine particle air pollutant exposure and longer menstrual cycles. (Photo: Dmitry Makeev, Wikimedia Commons, Public Domain CC BY-SA 4.0)

Fine particulate air pollution, or PM2.5, has been linked to many health consequences such as cancer, respiratory diseases, and cardiovascular damage. Now researchers are finding connections between exposure to this air pollution and longer menstrual cycles. Ashanti McLean reports in this note on emerging science how period tracker app data helped make the link.

Transcript

DOERING: The health consequences of burning fossil fuels go beyond what you might expect, as Ashanti McLean reports in this week’s note on emerging science.

[SCIENCE NOTE THEME]

MCCLEAN: In our post-industrial revolution world, where fossil fuels continue to power our cities, air pollution follows closely behind. Health consequences such as cancer, respiratory diseases, and cardiovascular damage are well documented when people are exposed to high levels of the fine particulates known as PM2.5. This air pollution is emitted by coal and gas fired power plants, gas powered vehicles, and wildfires.
But research has begun to uncover another potential consequence—one that may affect human reproduction. In a study published in The Lancet Planetary Health, a research team from the MIT Sense-able City Lab and the University of Colorado Denver, collaborated with a menstrual period tracker app called Clue. They examined the cycles of 92,000 users with female anatomy across the US, Mexico, and Brazil, and discovered a significant link between fine particulate air pollution and unusually long menstrual cycles, or those lasting longer than 38 days. Coauthor of the study, Dr. Priyanka deSouza stated that “for every 10 micrograms per meter cubed increase in long-term PM2.5, the odds of a long cycle were about 3.6% higher.” Like any other bodily function, reproductive health is an important aspect of overall wellbeing. While more research is needed, as one of the first to use a menstrual tracking app to obtain cycle data, this study provides compelling evidence that air pollution from smoke stacks and tail pipes may be linked to more health consequences than we thought. That’s this week’s note on emerging science. I’m Ashanti McLean.

 

Links

Read more about this human reproductive health study at the Clue app website

Find this article at The Lancet Planetary Health