Mycoplasma hominis, Ureaplasma urealyticum, and Ureaplasma parvum are bacteria commonly found in the urogenital tract. However, their pathogenicity in sexually active or obstetrical patients remains controversial. Therefore, determining the significance of screening and treatment for these organisms is challenging, unlike Mycoplasma genitalium which now has well-defined management guidelines. We conducted a review of the literature to clarify the clinical significance of detecting these micro-organisms. It is crucial to carefully select the few cases that warrant further investigations, in order to mitigate the risks of overdiagnosis and overtreatment.