Red discharge from underwear during non-menstrual period, without odor, may be related to ovulation bleeding, taking birth control pills and birth control ring displacement. 1. Ovulation bleeding: female ovulation is usually 14 days before the next menstrual period, if there is a small amount of red discharge during this period, there is no special smell may be ovulation bleeding, usually short duration, bleeding will be less than the menstruation, sometimes accompanied by a slight pain in the lower abdomen, and the decline in the level of estrogen, a physiological phenomenon, generally no need for treatment. 2. Taking contraceptive pills: withdrawal bleeding can occur, pay attention to good pubic hygiene, prevent gynecological diseases. At the same time, you should take contraceptive pills correctly according to the doctor’s instructions to prevent contraceptive failure and endocrine disruption. 3. Displacement of the birth control ring: If there is a birth control device in the body, it is necessary to pay attention to whether the birth control device is dislocated or not. Displacement of the birth control device may stimulate the endometrium, resulting in red secretion, which is usually not accompanied by a bad smell. There may be other reasons for the red discharge from the underwear during non-menstrual periods without odor, so you should go to the hospital in time to complete the relevant examinations and give targeted treatment under the guidance of a professional doctor to clarify the cause of the disease.