What Is Mycoplasma Genitalium?

Medically Reviewed by Traci C. Johnson, MD on March 09, 2024
3 min read

Mycoplasma genitalium (MG) is a type of bacteria that can cause an STD. You get it by having sex with someone who has it. Even if you don’t go “all the way” with vaginal sex, you can get MG through sexual touching or rubbing.

Scientists have known about this bacteria since the 1980s, but a recent study showed that more than 1 in 100 adults might have it.

MG doesn’t always cause symptoms, so it’s possible to have it and not know it.

In men, the symptoms are:

  • Watery discharge from your penis
  • Burning, stinging, or pain when you pee

The symptoms for women are:

  • Discharge from your vagina
  • Pain during sex
  • Bleeding after sex
  • Bleeding between periods
  • Pain in your pelvic area below your belly button

Unlike other STDs, there is no test for MG that the FDA has approved. But if you or your doctor think you might have it, you can get a nucleic acid amplification test (NAAT).

For this test, you might have to give a sample of your pee. Your doctor might also use a swab to take a sample from your vagina, cervix, or urethra, the tube that carries your pee out of your body.

MG can cause a number of complications:

Scientists aren’t sure if an MG infection can make it hard for men to get a woman pregnant.

MG can be a tricky problem to treat. Common antibiotics like penicillin kill bacteria by damaging a germ’s cell walls. But MG bacteria don’t have cell walls, so these drugs don’t work very well.

Your doctor might try azithromycin (Zithromax, Zmax) first. If that doesn’t work, your doctor might give you moxifloxacin (Avelox).

After a month, you can get another test to make sure the infection is gone, but it’s not a good idea to get routine tests if you don’t have symptoms from MG. If you still have symptoms and you still have the disease, you’ll need to get more treatment.

Your doctor might also focus on treating the other conditions MG can cause, like urethritis, PID, or cervicitis.

Your sex partners should talk to their doctors about getting tested and treated and so they don’t infect other people or give it back to you. You can still get MG again even when you’ve already had treatment for it.

Condoms can reduce your chance of getting MG, but they can’t guarantee you won’t get it. If you have the disease, avoid having sex for 7 days after you start treatment so you don’t infect others.