Mycoplasma is a group of microorganisms that are between bacteria and viruses in size, but different from them. Since mycoplasma was recognized in 1898, it was soon discovered to be one of the important risk factors for non-gonococcal urethritis in men and non-gonococcal genitourinary tract infection in women. As a result, with the increasing attention paid to it, testing for mycoplasma gradually became a routine screening program. At the same time, more and more people are being tested positive for mycoplasma in their genitourinary tract without any discomfort, i.e. the presence of mycoplasma infection. Mycoplasma is a separate type of microorganism and there are more than 80 species in nature, most of which are parasitic outside of cells, such as the genitourinary tract, respiratory tract, oral cavity, and intestinal mucosal surfaces. However, only three of them, which are considered to be associated with genitourinary tract pathogenesis, are Mycoplasma solium, Mycoplasma humanum and Mycoplasma genitalium. Mycoplasma urealyticum and Mycoplasma histolytica are the main ones examined clinically. In the past, we believed that genitourinary tract infections caused by Mycoplasma solani (e.g., non-gonococcal urethritis, non-gonococcal genitourinary tract infection, etc.) were mostly found in people who were sexually active and had more sexual partners, and were therefore considered to be sexually transmitted diseases. However, recent studies have found that although Mycoplasma solium is more likely to be found in the genitourinary tract in people who are more sexually active than in those who are less sexually active, it can also be found in the genitourinary tract of women who do not have any sexual intercourse. Moreover, in these individuals there are no uncomfortable symptoms. Therefore, it is not really appropriate to attribute all genitourinary tract infections to mycoplasma infection. In fact, a growing number of studies have shown that mycoplasma in the genitourinary tract is nothing more than a conditional pathogen. When the body’s resistance decreases, it causes a person to develop the disease, and vice versa. Therefore, a positive test for mycoplasma does not require treatment for everyone. In general, only the following three conditions require treatment: i. The patient has clinical symptoms, such as the presence of urethritis, cervicitis and other symptoms. For patients with urethritis, the manifestations are redness and swelling of the urethral orifice, itching, burning pain, urgency, frequency and difficulty in urination; urethral discharge is often plasma or mucus, and when not urinating for a long time or before the first urination in the morning, the discharge overflows and pollutes the underwear or cakes into a paste that seals the urethral orifice. However, in clinical practice, fewer female patients exhibit symptoms of UTI. For female patients, if the clinical manifestation is cervical congestion, erosion, increased discharge, and vulvar itching, lower abdominal discomfort and other symptoms, but in addition to positive mycoplasma test, all other pathogens are negative, and no other cause can be found to explain, such patients are in need of treatment, because some serotypes of Mycoplasma solani are pathogenic. Second, those who need to have children. In some infertile patients, mycoplasma infection may be a factor in infertility. In addition, if mycoplasma is infected in the pelvis, uterus or fallopian tubes, it can lead to pelvic inflammatory disease, endometritis and tubal inflammation in female patients, causing tubal blockage and inducing ectopic pregnancy or infertility. Third, after both sex partners have sex, one party repeatedly has clinical symptoms while the other party does not have any discomfort, but both parties are positive for mycoplasma, other than that there is no other pathogenic infection, and the asymptomatic party should also be treated at the same time. Except for the above three cases, treatment is not necessary for those who are positive for mycoplasma. On the contrary, over-treatment may lead to the development of drug resistance in these mycoplasmas. For patients who need treatment, tetracyclines such as doxycycline and minocycline, macrolides such as erythromycin and azithromycin (and quinolones are available. In general, men usually need to take the medication for 7 to 14 days and women need to take the medication for 10 to 14 days. After the medication is used strictly according to the doctor’s prescription and the self-perceived symptoms are reduced or disappeared, a review should be conducted at the hospital. If three consecutive mycoplasma tests are negative, it is considered cured. In this process, the most important thing is to use the medication according to the standard, do not just stop or change the medication, and should not use several drugs at the same time, to avoid mycoplasma drug resistance. During the treatment period, it is not advisable to have sex or drink alcohol, and the spouse or partner should be examined and treated at the same time (with or without symptoms). If you have sex, you should always use a condom at the beginning of sex, rather than putting it on halfway or at the end. In China, a survey of Mycoplasma solium infection in different populations found that 73% of mid-term pregnant women tested positive for Mycoplasma solium. However, when we say that mycoplasma infection may be associated with low birth weight babies and may also have some association with postpartum fever, etc., we mean that the mycoplasma-ungui infection occurs in the amniotic cavity. In contrast, clinical tests for mycoplasma are performed by taking cervical or vaginal secretions, and a positive result can only represent an infection of the vagina or cervix, and is not equivalent to an infection of the uterine or amniotic cavity. Therefore, as mentioned earlier, even if the test for mycoplasma is positive, as long as there are no symptoms, treatment is not necessarily necessary for the pregnant woman. This is because at this point there is essentially no therapeutic significance. Therefore, for pregnant women, as long as there are no symptoms, they can be left untreated. Once symptoms appear, they need to be treated with medication on a strictly regular basis. As for the child, there may be concerns that the child will be infected by mycoplasma during vaginal delivery. Yes, mycoplasma infection can occur during vaginal delivery due to inhalation of vaginal secretions, but not every child will be infected during vaginal delivery and only intensive monitoring is needed. Moreover, since Mycoplasma urealyticum only lives in the genitourinary tract, this kind of inhalation infection is transient and usually does not affect the child as long as it is treated promptly. It is true that mycoplasma infection in the genital tract is related to the age of first sexual intercourse, the degree of sexual activity and the number of sexual partners, but it cannot be said that a positive mycoplasma test must be caused by an unclean sexual life. In fact, in addition to sexual intercourse, there are also other indirect infections, such as the use of public toilets, bathtubs, bathrobes, bath towels, etc.; the mother is infected with the disease and transmitted to the fetus and newborn through the birth canal. However, the chance of this indirect infection is not very high. Most importantly, normal married life is also a source of infection. Some studies have shown that among couples who have normal sex, the positive rate of vaginal or/and cervical tests for Mycoplasma solium reaches 50-60% in women and about 20% in men. Therefore, it is not surprising that infection with Mycoplasma solium occurs in normal couples who have sex, especially when resistance is low (e.g., after alcohol abuse). Of course, this does not mean that some people can use this as a shield for unclean intercourse and cheating behavior. In conclusion, mycoplasma is a common parasitic microorganism of the urethra and genitourinary tract, and we currently consider it more as a conditionally pathogenic bacterium that causes disease only when the body’s resistance is reduced. In fact, this explains why many people are cured and then get sick again some time later, making people upset and think that mycoplasma infections are recurrent and incurable and do not hesitate to make great efforts to treat them. We still emphasize that we don’t need to worry too much even if mycoplasma reacts positively.