![\"STI](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2026\/04\/SEC_170095770-ec63.jpg\")
\n\t\tLess than 15% of people have heard of Mgen (Picture: Getty Images)<\/p>\n
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\n\t\tLess than 15% of people have heard of Mgen (Picture: Getty Images)<\/p>\n
You\u2019re likely familiar with chlamydia<\/a>, which runs rampant throughout the UK in hotspots like Liverpool<\/a>, which has more than 21,000 infected residents.<\/p>\n But what if we told you there\u2019s another lesser-known STI<\/a>, with similar infection rates, that has gone under the radar.<\/p>\n Mycoplasma genitalium (also known as Mgen or MG) was discovered in 1981, 74 years after scientists discovered chlamydia, but a reliable test for it was only produced in 2017.<\/p>\n Worryingly, just 15% of Brits have heard of Mgen, according to LloydsPharmacy Online Doctor, despite it affecting 500,000 Brits, about 2% of the sexually active population.<\/p>\n The reason Mgen is so prevalent is because it\u2019s often symptomless, just like HPV<\/a>, but it\u2019s also antibiotic resistant. So Metro spoke to doctors to get the lowdown on this elusive STI.<\/p>\n What is Mgen?<\/p>\n Mgen is a sexually transmitted bacterial infection, caused by the mycoplasma genitalium bacteria.<\/p>\n \u2018It affects the urethra, cervix and sometimes the rectum, and behaves a bit like chlamydia, but it\u2019s less well known and harder to treat,\u2019 Dr Nikki Ramskill, founder of The Female Health<\/a> Doctor Clinic, tells Metro.<\/p>\n \t\t \t\t\t\tSex. Love. Modern Mess. Listen to new Metro podcast Just Between Us\t\t\t<\/p>\n X Factor icon Diana Vickers and writer, broadcaster, and LGBTQ+ advocate Jack Guinness dive into your wildest sex, love, and dating dilemmas \u2013 every Tuesday.<\/p>\n Listen\u00a0wherever you get your podcasts<\/a> or watch on YouTube. And be sure to follow and subscribe so you never miss an episode.<\/p>\n You can also join the fun on our WhatsApp Group Chat\u00a0here<\/a>\u00a0\u2013 share your dilemmas and Diana and Jack may just give you a call. \u00a0<\/p>\n<\/p>\n You can contract Mgen\u00a0by having unprotected vaginal or anal sex with someone who has the infection, although researchers are still determining whether it can spread through oral sex<\/a>.<\/p>\n If you\u2019re wondering why you aren\u2019t routinely tested for it like other STIs, there\u2019s one simple reason.<\/p>\n \u2018Mgen isn\u2019t included in standard STI screening unless there\u2019s a specific reason, like persistent symptoms,\u2019 Dr Ramskill, from Doctify, adds.<\/p>\n \u2018Widespread testing could lead to unnecessary antibiotic use, which is a real concern given how resistant this infection already is.\u2019<\/p>\n What are the symptoms of Mgen?<\/p>\n Mgen is slightly more common in women than in men, according to the British Association of Sexual Health, and it\u2019s usually symptomless for 50 to 70% of women, and 80% of men.<\/p>\n However, some people show symptoms one to three weeks after infection, so here\u2019s what to look for.<\/p>\n Someone with symptoms may notice:<\/p>\n Pain or burning when passing urine<\/p>\n Unusual vaginal discharge<\/a><\/p>\n Discharge from the penis<\/p>\n Pelvic pain or discomfort<\/p>\n Bleeding after sex<\/p>\n Pain in the testicles<\/p>\n Genital itching<\/p>\n Inflammation in the rectum<\/p>\n \u2018The tricky part is that these symptoms look very similar to other common STIs,\u2019 Dr Ramskill explains.<\/p>\n According to doctor Babak Ashrafi, a Superdrug Online Doctor<\/a>, having another STI and unprotected sex both increase the risk of infection, too.<\/p>\n \t\t \u2018With more than half of Brits having unprotected sex and not having been tested for STIs like gonorrhoea, it\u2019s a concern,\u2019 he tells Metro.<\/p>\n Is Mgen dangerous?<\/p>\n Like many other conditions, if left untreated it has the potential to cause more problems.<\/p>\n \u2018Untreated MG can cause serious complications,\u2019 Dr Ashrafi explains. \u2018In men, it\u2019s linked to epididymitis <\/a>(where a tube behind the testicles becomes swollen and painful) and proctitis (inflammation in your rectum).\u2019<\/p>\n Dr Ramskill says it\u2019s also linked to persistent urethritis, which is pain at the top of the penis.<\/p>\n \u2018In women, it can lead to cervicitis (inflammation of the cervix) and pelvic inflammatory disease (PID)<\/a>, which in some cases may affect fertility and cause spotting in between periods,\u2019 she adds. \u2018It\u2019s not something to ignore if symptoms are ongoing.\u2019<\/p>\n How is Mgen treated?<\/p>\n Typically, antibiotics would be used to treat an STI like Mgen, although Dr Ashrafi says this infection is becoming \u2018worryingly resistant\u2019 to them, meaning it could be classed as a \u2018superbug\u2019.<\/p>\n \t\t \u2018In some regions, resistance rates exceed 90%, making MG one of the fastest-growing antibiotic-resistant STIs,\u2019 he explains.<\/p>\n \u2018Treatment now usually requires a two-stage antibiotic approach, typically doxycycline followed by azithromycin or moxifloxacin.\u2019<\/p>\n But antibiotics do still work, Dr Ramskill reassures us, we just have to be much more careful and specific about how we use them.<\/p>\n Of course, if you want to avoid Mgen while having sex, the simple answer is to use a condom and get tested regularly if you\u2019re sexually active.<\/p>\n Do you have a story to share?<\/p>\n Get in touch by emailing MetroLifestyleTeam@Metro.co.uk<\/a>.<\/p>\n Arrow Arrow Arrow![\"Asian](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2026\/04\/GettyImages-1506272867.jpg\")
\n\t\tPainful inflammation in the rectum and testicles can be symptoms (Picture: Getty Images)<\/p>\n![\"Gynecologist](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2026\/04\/GettyImages-2187869349.jpg\")
\n\t\tYou will only be tested for Mgen if you don\u2019t test positive for other STIs (Picture: Getty Images)<\/p>\n![\"Woman](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2026\/04\/GettyImages-1061241638.jpg\")
\n\t\tProtected sex is the only sure fire way to keep yourself safe from STIs (Picture: Getty Images)<\/p>\n
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