If there is light red discharge on the underwear, consider having vaginal bleeding. You should specifically check the cause as well as the location of vaginal bleeding, such as cervical bleeding, cervical erosion, cervical polyps, and cervical cancer, which can cause vaginal bleeding and usually require gynecological examination, cervical cancer screening, HPV testing for human papilloma virus, and colposcopic cervical biopsy for clear diagnosis. Uterine bleeding should also be considered. For example, if there is endocrine disorder causing abnormal vaginal bleeding, further hormone six tests can be done to understand the hormone level in the body and select medications to regulate menstruation to stop bleeding. In addition, there are also abnormal uterine bleeding caused by endometrial lesions, further hysteroscopic endometrial biopsy is needed to clarify the diagnosis and choose surgery or medication according to the result. Endometrial cancer requires hysteroscopy and endometrial biopsy to clarify the diagnosis and decide the next treatment plan. Uterine fibroids and adenomyosis may also cause abnormal uterine bleeding, which needs to be further ruled out by gynecologic ultrasound. In conclusion, if this situation occurs, it is recommended to go to a regular hospital for appropriate examination.