You cannot use tampons during pregnancy, and I wouldn't use yoghurt either - you're not to use of put anything down there unless it's okay'd be a doctor because there is the risk of introducing new bacteria. As long as you're in the second trimester then it's okay to treat - the type of antibiotics needed to treat it cannot be used in the first trimester, only the second. Consult your doctor.
I was also concerned about this. I have used yogurt tampons in the past for BV, which was successful. Have you ever tried it and is it OK during pregnancy?
At the beginning of my pregnancy I had BV and the doctor wasnt able to treat me til I was over 12wks. Now im 25w6d n im fine. The BV has not returned but it's common
A bacterial infection can be normal whether a women is pregnant or not and shouldn't affect your baby at all. Try not to worry. As long as it's being treated it will clear up and all will be well.