I had the same problem too, I was on Tri
Sprintec (generic of Ortho TriCyclen) and I was getting yeast infections all the time. My doctor said I didn't have enough good bacteria so she told me to go out and buy some lactobacillus supplements (you can buy them at your average vitamin store). They work great, I take them 3 times a week (Mon, Wed, Fri) and I've been great. Also though- are you sexually active? That could help to contribute to your yeast infections. If so, there are a couple other steps you should take to help prevent yeast.