Scientists are only just confirming that womens menstrual cycles can affect how well drugs work

It’s about time.With as many advances as we’ve seen recently in women’s health — from endometriosis being able to be diagnosed without surgery, to completely rethinking and renaming PCOS, now more accurately, PMOS — we still have a long way to go in terms of understanding how medications affect the sexes differently.It’s often only after a drug is released do we learn women might be affected totally differently from men — as with the case for two recent major studies.Specifically, the new research points to the role of estrogen, which naturally ebbs and flows over the course of a menstrual cycle.Changing levels of estrogen has major impacts across the entire body under normal circumstances.Introduce medication into the mix, and it becomes a whole different ballgame.“For too long, the menstrual cycle has been treated as background noise in health research,” said Poppy Cooper, an author of one of the recent studies.

“This work is part of a growing shift in that thinking and a recognition that the menstrual cycle has impacts beyond reproductive health.”Here’s which medications researchers are learning could be impacted by menstrual changes.After the COVID-19 vaccine was rolled out in 2021, people quickly caught on that the shot affected women differently.Researchers found that there were “small and temporary” changes to menstrual cycles after women were vaccinated — on average, the entire cycle (about 28 days) increased by about half a day.It took another five years to find that where women were in that cycle when they got the vaccine affected how effective the vaccine was.Researchers in a June study found that women who were vaccinated at the follicular phase, about a 10-20 day stretch that starts on the first day of bleeding, were 35% more likely to get side effects than those who got the shot in the luteal phase, the span just before the period comes back.People vaccinated during the follicular phase avoided infection for 200 days long...