infection during pregnancy. help me please...

I was diagnosed with trichomonas vaginalis (10th week of pregnancy). My doctor prescribed vaginal suppositories (Neo-Penotran Forte) which has a generic name of Metronidazole + Miconazole Nitrate. When I read the instructions that came with the medication, it says there that it shouldn't be taken during the first trimester. But my ob prescribed it.   According to her, suppositories are safer than oral medications. But I'm still hesitant. Has anyone here experienced the same situation I'm having right now? What should I do? Should I trust the label? Or should I just trust her? Please share your experience...