Can boric acid caplets cause vaginal bleeding? I had on going yeast infections, spent countless of time and money on perscriptions and nothing worked. I read how Boric Acid is very effective in getting rid of yeast infections. After a week of taking it, I had my period, so I stopped taking the Boric Acid. After my period, I resumed to the Boric Acid capsuals. Now, I notice that fresh blood is on the toilet paper when I wipe. I will be 43 years old in a couple of months. I also had deep penetration intercourse the other day, but it was not rough.