If you notice a thin
white or gray
discharge with a fishy smell after sex (when the
discharge mixes with semen), you may have a different kind of vaginal infection called bacterial vaginosis.
If your discharge is yellow or green and frothy with an unpleasant odor, you may have trichomoniasis, a common sexually transmitted infection. Other possible symptoms of trichomoniasis (or trich) include a red, irritated, or itchy vulva or vagina and discomfort while urinating or during intercourse.