If the discharge has a fishy odor without itching, it is most often a vaginal inflammation caused by bacterial vaginosis, which often manifests itself as a localized discomfort in the vulva and an increase in discharge, yellowish color, relatively thin discharge, and a big fishy odor in the discharge. Once this happens, if the leucorrhoea test is positive for BV, treatment with metronidazole will cure it after about 7 days. In addition, if bacterial vaginosis is ruled out, the fishy smell of discharge may be caused by inflammation of the pelvis, cancer of the endometrium or cancer of the cervix.