Can bacterial vaginosis be caused by a method other than sex? my friend got it at a time when she was not sexually active. she's had 2 partners ever.

Yes it can: Bacterial vaginosis is not really an infection but rather an overgrowth of normal anaerobic vaginal bacteria. The vagina can correct itself but there are medications that can be used to treat it. It is not a sexually transmitted infection.

Not by sex: Bacterial vaginosis (BV) is not caused by sex, although it is more common in women who are active. BV is not really an infection, but an imbalance in the normal bacteria in the vagina. The healthy bacteria aren't doing well, so bad bacteria overgrows, causing the symptoms. Antibiotics suppress the bad bacteria, but it's important to do probiotics, like acidophilus (in yogurt) to restore the good.