Mycoplasma genitalium is a small pathogenic bacterium that lives on the ciliated epithelialcells of the urinary and genital tracts in humans. Its existence was first reported in 1981, and was eventually identified as a new species of Mycoplasma in 1983. It can cause significantmorbidity in men and women, and is a co-factor in HIV transmission. It is still controversial whether or not this bacterium is to be recognized as a sexually transmitted pathogen. Specifically, it causes urethritis in both men and women, and also cervicitis and pelvic inflammation in women.