Help please tmi

So since I got pregnant I been getting a lot of discharge and itchiness well doctor prescribe me a 7 day treatment and it didn't work well 2 weeks after I had sex with husband and his penis was full of white discharge it's not a Yeast or an infection doctor just had said it over growth bacteria . I read on here a girl said she put a tampon up her vagina with oxide water I'm thinking of doing that is it safe currently 30 weeks pregnant