Story highlights Though experts have known of MG's existence since the '80s, we now know it spreads through sexual contact

Just like many other STDs, MG is often asymptomatic

As if there's not enough bad STD news to worry about already—a recent study suggests there's a new sexually transmitted infection in town. Introducing: mycoplasma genitalium, or MG.

Though experts have known of MG's existence since the '80s, the new paper published in the International Journal of Epidemiology reveals that the bacterial infection, which resides in the urinary and genital tracts, likely spreads through sexual contact.

To reach their findings, researchers at University College London, examined urine samples of 4,507 men and women between 18 and 44 years old who were sexually active with at least one partner. Of these participants, 48 women and 24 men were diagnosed with MG. However, when the researchers tested urine samples from about 200 teenagers who had never had sex, zero tested positive for the infection.

We spoke with Raquel Dardik, MD, a clinical associate professor at NYU Langone's Joan H. Tisch Center for Women's Health, to get the facts on the "new" STD.

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