Thank you I appreciate it!
I looked it up for you, and they advise against using it unless it is absolutely needed and there is no safer alternative (like some antibiotics). Main reason they advise against it is because it hasn't been tested enough, so they aren't sure about the safety of the drug. They also say: is you do take it, take it after the 4th month of pregnancy and take a one time dose.
If you are worried about taking it, you can call your doctor, or gynaecologist or so (or both), to make sure this is the best you can do right now (getting rid of that infection may be worth the risk). But i doubt your doctor would prescribe it if he didn't think it really necessary. And most likely your baby will be fine.
I'm in my third trimester, and this is my first baby, I get very worried fast. Did anyone take it orally?
I also took metronidazole but was prescribed it vaginally! This was early in my pregnancy and I never had any issues with it.
I didn't have to take pills but gel injection doctor wouldn't prescribe you something that was more harmful then the actual infection.