Fishy odor in the lower body is caused by bacterial vaginitis as well as acute cervicitis, which is caused by abnormal vaginal secretions. However, a very small number of patients with reproductive system tumors, such as cervical cancer, endometrial tumors, ovarian cancer, etc., may also have a fishy smell in the lower body. Most of the reproductive system tumors will be accompanied by other uncomfortable symptoms, such as watery vaginal discharge or abnormal vaginal bleeding. If you have a fishy smell in your lower body and need to make a clear diagnosis, you need to carry out a leukorrhea examination in time, and for women who have sexual intercourse and those who have cervical lesions, you also need to carry out an exfoliative cell examination of the cervix, or even carry out a biopsy of the cervix. If necessary, it is also necessary to carry out a biopsy of the endometrium, mainly to exclude the possibility of malignant tumors of the reproductive system, and pay attention to changing underwear.