Does estradiol cause yeast infections?

Yes, yeast infection (or vaginal candidiasis) is a common side effect of estradiol. It is not so much the estradiol as the changes that the hormone causes within the vagina that makes conditions favorable for the overgrowth of Candida (or yeast) First of all you need to treat the infection and I would recommend you see your Dr rather than try OTC treatments. If the estradiol is not something you can do without then you may need to discuss ways of discouraging yeast overgrowth. Some women are helped by probiotics, some women find avoiding white flour and white sugar products helpful. It is something you should discuss with your provider though as to what your best options are.