There are three main things to consider when there is yellow leukorrhea in the underwear with crusting: first, the patient does not change the underwear regularly. In general, if the panties are changed 1 time in 1 day and the leukorrhea is normal, there should not be this situation. If the panties are not changed diligently, 3-5 days to change 1 time, or even 1 week to change 1 time, this situation will occur, which is normal. Second, physiological leukorrhea increase. During ovulation, before menstruation and after pregnancy, due to changes in hormone levels, resulting in strong secretion of reproductive secretory glands, there will be a physiological increase in leukorrhea. In this case, the leukorrhea is mostly light yellow, and there is no odor or itching, which is normal and does not need to be treated. Third, pathological leukorrhea increase. Pathological leukorrhea increase, mostly seen in gynecological inflammatory diseases, need to do gynecological internal examination, and take the leukorrhea to do laboratory tests to determine the location and type of inflammation, symptomatic treatment.