The STI Files: Mycoplasma Hominis

Stat: First isolated from the human genital tract in 1937external link, opens in a new tab, M. hominis is much more common in those born with vaginas than for those born with a penis⁠ (penis: One of the two external reproductive organs of people often assigned male at birth.) .

What is it exactly? Mycoplasma hominis is a self replicating bacteria, commonly spread through sexual⁠ (sexual: About or relating in some way to sex or sexuality.) contact, that takes up residence in the urinary tract and genitals⁠ (genitals: Body parts that are generally, culturally, scientifically or personally considered to be external sexual or reproductive organs.) and causes infections. Much like Ureaplasma urealyticum, it is a type of genital mycoplasma, a type of bacteria that is unique in that it lacks rigid cell walls, which can make common antibiotics ineffective treatment for some cases. Given where it resides and replicates, it mainly causes urinary and reproductive organ infections as well as neonatal infections.

About how many people have it? Rates of M. hominis vary greatly from study to study. One estimate states that it may be found in 20-50% of people with vaginas or cervixes of reproductive age. 

How is it spread?  It can be spread from partner⁠ (partner: In a sexual context, a person with whom someone is having some kind of sex. The term “partner” can be used for all kinds of relationships, not just serious ones. “Partner” can also mean the person someone is with in a romantic or familial partnership.) to partner through vaginal, anal and oral sex⁠ (oral sex: Use of the mouth, lips or tongue for sexual stimulation. Cunnilingus (“going down on”), fellatio (“blowjobs”) and analingus (“rimming”) are some common kinds of oral sex.) . It also can be spread from a birthing parent to their baby via exposure to amniotic fluid.

What are its symptoms? Like most STIs, it frequently occurs without symptoms, thus going undiagnosed. When there are symptoms, they can include irregular discharge⁠ (discharge: In the context of sex and sexual health, any number of fluids which come from the genitals. Plenty of genital discharge is healthy, while some discharges can be symptoms of illness.) , whether that be penile, vaginal or rectal, and urinary complications, such as changes in frequency, urgency and a burning sensation

How is it diagnosed? While not routinely tested for, it can be diagnosed using a special molecular method or PCR test.

Is it treatable? M. hominis is treatable, though it is trickier to treat than your typical bacterial STI⁠ (STI: Sexually transmitted infections: illness, infection and/or disease which is often or can be transmitted through sexual or other intimate contact, like HIV, Chlamydia or Herpes. Some people call STIs STDs.) due to its lack of cell wall. This usually just means a prescribing provider will opt for a less common type of antibiotic.

Is it curable? So long as one follows their healthcare provider⁠ (healthcare provider: A qualified person to provide sound physical and/or mental healthcare, such as a doctor, nurse, clinician, counselor, medical assistant, midwife or other healthcare professional.) ’s guidance, M. hominis is perfectly curable. A full course of antibiotics, taken as directed, will usually eradicate it, and temporarily abstaining from sexual contact with others during treatment is what is most effective at stopping it from spreading.

Can it affect fertility⁠ (fertility: The ability to become pregnant or other things having to do with becoming pregnant (eg, “the fertility clinic”).) ? M. hominis and fertility’s intersection is still being studied. However, it is known that there is a link between this bacteria and reproductive complications, such as pelvic inflammatory disease, or PID⁠ (PID: Pelvic inflammatory disease is a serious infection of the uterus, fallopian tubes and other reproductive organs, most often caused by an untreated STI like chlamydia and gonorrhea.) . When left untreated, then there is risk of infertility. 

Can it cause death? No.

How can we protect against it? If you choose to engage in genital sexual contact, it is best practice to use barrier methods, such as condoms and dental dams. This reduces the spread of fluids, and the likelihood of infection⁠ (infection: When harmful microbes, or germs, or harmful levels of microbes/germs, enter the body and multiply, causing illness. The common cold, flu viruses, sexually transmitted infections, chickenpox, impetigo, rabies and diphtheria are some kinds of infections.) . If it was not your choice to engage in genital sexual contact and you believe you are at risk of infection, testing and treatment options are still available to you.