Every month towards end of my menstruation it's very itchy and odor. is it yeast or bv? i've been treated for both in past, but this is still ongoing.

Discharge: Discharge and vaginal discomfort towards the end of your cycle is more likely bacterial vaginosis. Blood can alter the pH of the vagina and predispose to BV. Using tampons for long periods of time is also a risk factor. I suggest changing tampons every 4 hours and not using tampons at night. Visit your GYN when you're having symptoms to give you a more definitive answer.