I would either use Monistat or ask your doctor for the topical cream prescription. Ive had basic insurances that cover that so that I only pay about $10 for it. I've had 3 yeast infections and have never taken a pill for it.
Monistat 7 is the safest thing to use during pregnancy. I used it in early pregnancy with my 3 girls and there were healthy. if it was me don't use that prescription, just the Monistat. My doctor that I had, now I'm having my 5th baby and they say Monistat is the safest to use and you can even use the cheapest brand, it's all the same.