Boil your menstrual cups

The science:

When researchers tested menstrual cups and tampons for bacteria, they found that the cups were more likely to harbor Staphylococcus aureus, a strain known to cause toxic shock syndrome (TSS). The study was recently published in Applied and Environmental Microbiology.

Expert insight:

According to the American College of Obstetricians and Gynecologists, women should remove their menstrual cups (a reusable, environmentally friendly choice) every eight to 12 hours. But keeping the cup in for that long is associated with TSS, says study author Gérard Lina, MD, Ph.D., president of the French Society of Microbiology and professor of medicine at the University of Lyon in France. When outside air enters the vagina, it encourages bacterial growth. Cups trap more air than tampons do because of their size and shape, the authors say, creating the perfect conditions for bacteria to thrive. Your risk of TSS is relatively low with either product, but there are steps you can take to minimize it further.

The bottom line:

Lina recommends replacing tampons and menstrual cups every four to six hours. To get rid of lingering bacteria, boil your silicone cup for five to 10 minutes at the end of your cycle or for a couple minutes every time you remove it, he says.

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