Q: My doctor told me I had bacterial vaginosis. I took the entire dosage of medication. On the last day of my medication, I had sex and it hurt. It's been a week and I'm still sore. I thought that I might have a yeast infection and used Monistat, but it stung. I've heard you can have bacterial vaginosis for years. Is this true? Is there a way to get rid of it for good?

A: First of all, it's not clear that the soreness and stinging you noted are due to bacterial vaginosis (BV). BV often causes an abnormal vaginal discharge with an unpleasant odor, but is not typically painful. The discomfort you experienced might be due to lack of adequate lubrication during sex, sensitivity to latex condoms or another cause of vaginal infection or irritation, such as trichomoniasis.

Second, BV is not usually considered to be sexually transmitted and treatment of male sexual partners for BV is not recommended. The exact cause of BV is not known, but seems to result from an imbalance in the growth of multiple bacteria in the vagina, associated with a change in the vaginal pH, which becomes less acidic and more neutral. Preventive measures include avoiding exposure to semen by using condoms consistently and completing the full course of antibiotic therapy, even if symptoms resolve. Avoid vaginal irritants such as douching, bubble baths, feminine hygiene sprays, and deodorant tampons, all of which can alter the normal bacterial flora and change the pH of the vagina.

If your symptoms continue, return to your doctor for further evaluation to find out the cause.

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