Leukorrhea is a fluid that is secreted from the vagina of a woman. The normal leucorrhea of women is colorless, odorless and transparent egg white, however, many women have yellowish leucorrhea with odor, which is actually a manifestation of some kind of gynecological inflammation, causing yellowish leucorrhea to consider many factors. The following are the 3 main reasons for the yellowing of the leucorrhea. 1, Trichomonas vaginalis This is the most common vaginitis, caused by Trichomonas vaginalis infection, Trichomonas vaginalis is an anaerobic parasitic protozoa, often parasitic in the genitourinary tract, mainly in the vagina in women, but also in the urethra, paraurethral glands, bladder and other parts, men are often parasitic in the urethra, prostate and other parts. The transmission of trichomoniasis is indirect, i.e. through baths, tubs, towels, swimming pools, toilets, clothing, medical devices, dressings, etc. The main clinical manifestations of trichomoniasis are increased amount of leucorrhea, itching, burning or painful sensation in the vulva and phallus, typical leucorrhea is yellowish green, foamy, thin and has a fishy odor. The symptoms of urinary urgency and frequency may be present when the inflammation invades the urethra. 2, mycotic vaginitis Mycotic vaginitis is one of the common vaginitis, often caused by Candida albicans infection, mostly seen in pregnant women and diabetic patients, long-term application of broad-spectrum antibiotics can make the normal vaginal flora imbalance, which is conducive to the growth and reproduction of mycobacteria susceptible to this disease, taking corticosteroids, immunosuppressive drugs and autoimmune disease patients susceptible to this disease, vitamin B6 deficiency, chronic wasting disease patients susceptible to Yellowing of the leucorrhoea. Young women wearing tight nylon pants can increase the humidity and temperature of the perineum, which is conducive to the growth and reproduction of mycobacteria. The main symptoms of mycosis vaginalis are increased leucorrhea and vulvar itching, often accompanied by a local burning sensation. The typical leucorrhea is curd-like (tofu crumb-like) or slightly yellow flaky, slightly smelly and adheres to the vaginal mucosa. Age-related vaginitis This disease is most common in older women who have been menopausal for many years. After menopause, ovarian function declines, endogenous estrogen is lacking, the genitalia atrophy, the vaginal epithelium becomes thinner, and local resistance weakens, making it easy for pathogenic bacteria to multiply and cause inflammation. The typical leukorrhea is yellowish, watery or purulent, with a foul odor and often mixed with a small amount of blood.