Blood in stool after chemotherapy for ovarian cancer may be the side effect of chemotherapy drugs, tumor metastasis in rectal area and so on. 1. Side effects of chemotherapeutic drugs: chemotherapeutic drugs can effectively kill cancer cells, but they also have relatively big side effects, and will kill part of normal cells in the body. Some patients will have bone marrow suppression in the process of chemotherapy, at this time, platelets will fall, spontaneous bleeding will occur, and in serious cases, there will be gastrointestinal bleeding, which will cause some big damages to the body. 2. Tumor metastasis to rectum: ovarian cancer may have metastasis, and the metastasis mainly takes the form of direct spread and abdominal implantation, which will involve the neighboring organs, and it may also be metastasized through lymphatic channels, and if the tumor is metastasized to the rectum, rectal cancer will also cause blood in the stool. If the tumor metastasizes to the rectal area, rectal cancer will also cause blood in stool. Blood in stool after chemotherapy for ovarian cancer may also be related to other reasons, such as anal fissure, hemorrhoids, etc., which should be communicated with doctors in time, and the cause of the disease should be clarified and then dealt with symptomatically.