The STI that's new and you've probably never heard of
Scientists have discovered a brand new sexually transmitted infection (STI).
Hundreds of thousands of people might not know they have Mycoplasma Genitalium - or MG.
It's been around since the 1980s but a new study has finally found a link between the bacteria and having sex.
Here's everything you need to know about the STI.
What are the symptoms?
It causes discharge, painful testicles and for women, bleeding after sex.
But 90% of men and more than half of women will have no symptoms at all.
Even so, there are things you can look out for, says Dr Pam Sonnenberg, who led the study into MG.
"In men, they would have symptoms of Urethritis - which would be a discharge or pain and burning when passing urine," she says.
"Women with MG are more likely to report bleeding from the vagina after sex."
Do I need to get tested?
The infection is so new that doctors are still working out what it can do to our bodies.
So, at the moment you can't get an MG test at your GP or sexual health clinic.
The scientists did test the urine of more than 4,500 people aged from 16-44 to find out if they had it.
But, Dr Sonnenberg believes it could be years before that's an option for everyone.
"There's no routine testing available, and we don't know what the implications will be," she says.
Who's most at risk?
According to the study, MG is most common in those who've had more than four sexual partners in the past year.
It's particularly important not to sleep around with more than one person at the same time too.
"The point we're making is to reduce the number of partners," says Dr Sonnenberg.
"But also overlapping partners because that's when the infection is spread from one person to the next."
How can I avoid getting MG?
The advice is the same as it would be for any other STI.
Always practice safe sex. That means using condoms and not sleeping around.