The absence of blood in the menstrual period and only brown discharge can be seen as a result of pregnancy, such as preterm miscarriage, ectopic pregnancy or biochemical pregnancy. Further examination of blood HCG, gynecological ultrasound and progesterone is needed. Menstruation without blood and only brown discharge can also be caused by damage to the endometrium, such as for patients with a history of uterine operations, such as abortion, curettage, diagnostic curettage, hysteroscopy, etc., resulting in damage to the endometrium; or Mycobacterium tuberculosis infection, resulting in destruction of the endometrium. In both cases, low menstrual flow and brownish discharge from menstruation may occur. There is no blood in menstruation, only brown discharge. In this case, the patient’s medical history and physical examination are needed to further clarify the diagnosis.