Menstrual cups
Researchers advise following strict rules of hygiene when using menstrual cups Flickr

Menstrual cups are a revelation - they're environmentally-friendly and cost considerably less than tampons or sanitary towels in the long-run.

Although menstrual cups, in one form or another, have been around since the 1930s, they've become more popular in the last five years in the UK with the introduction of Moon Cups.

But one question still remains - do they pose a health risk to women?

A study by researchers at a university hospital in Lyon suggests women who use menstrual cups may be more at risk of Toxic Shock Syndrome, a condition caused by bacteria getting into the body that is normally associated with tampon use.

The researchers collected used sanitary products to better understand the bacteria that causes TSS, staphylococcus aureus.

The final study, which analysed more than 700 used tampons and menstrual cups, found that the cups are more likely to increase the production of bacterial toxins.

This is because menstrual cups allow air to enter the vagina, which creates an environment for staphylococcus and bacterial toxins to thrive.

That being said, the researchers do not recommend giving up on menstrual cups - but follow strict hygiene rules.

They advise emptying the menstrual cup every four hours and cleaning it every six hours. As is the case with tampons, the researchers warn women to avoid using menstrual cups overnight while sleeping.

TSS is caused by staphylococcus or streptococcus bacteria, which live harmlessly on the skin, nose or mouth but cause serious problems if they get deeper in the body, where they can release toxins that stop organs working properly.

The NHS advises using tampons with the lowest absorbency suitable for your menstrual flow, or alternating tampons with sanitary towels or panty liners during your period.