Bacterial Vaginosis?

Has anyone been diagnosed with bacterial Vaginosis? My doc called this morning saying my Pap smear showed that I have BV. I have no symptoms. She prescribed me 500mg of Metronidazole twice a day. It says on the label not to take during the first trimester. I'm 12 weeks 3 days. I'm a little worried about taking it. But it seems that the benifits of the medicine out weigh the risk. Anyone else been through this? Any input would be helpful. Thanks!