I am 27 and sexually active. I have a light brown discharge that is slightly stringy and vaginal itching and slight vaginal swelling. I have had this problem on and off for over a year now, with it reocurring every couple months and lasting for about a week. When I have seen the doctor, she says she doesn't detect excess yeast, but treats me for a yeast infection. I have tested negative for STD's. I do skip periods once and a while by taking back to back birth control pill packs. Last time this occured I didn't seek treatment and it cleared up after a week. Please help!