Boric acid is a powerful pesticide and a poisonous antiseptic. It has been popular as an antiseptic for women to clear vaginal infections because it can kill bacteria that are resistant to antibiotics. So, it becomes a routine treatment if antibiotics fail to clear the infection.
Boric acid does not show significant poisonous effect on a woman who uses it, so it gives an illusion that it is harmless to women.
Certain infections, like BV, are recurrent. Recurrent means that it can heal by itself and occur again. If the healing happens after using boric acid, it provides an illusion that boric acid has worked. In fact, healing may occur by itself even without treatment. Only a product that can stop the recurrence is truly effective.
Although boric acid does not appear to harm women, it may have some unknown poisonous effects on women if used repeatedly for a long term because the product is a poison.
It is more poisonous to the male reproductive system because sperms are like little insects and are more sensitive to pesticides. For women who use boric acid routinely and have difficulty to conceive, boric acid may be the culprit of the infertility.
After using boric acid, it may kill all live forms in the vagina, including both good and bad bacteria. The normal vaginal microbiome can be wiped out. If good bacteria come back first, the infection is cleared. But if bad bacteria or yeast come back first, they can invade the vacant land without protection from good bacteria. This is a common reason why boric acid often fails to clear infections. As soon as you stop using it infections may come back and become worse.
Inability to clear vaginal infections in some women may result in more frequent use of boric acid. This may result in more severe infections and more frequent use of boric acid. As a result, repeated use of boric acid may cause women to become trapped in the cycle of infection and more severe infection without an end.
If you want to learn more about boric acid, here is link:
https://www.neueve.com/blogs/blog/four-reasons-not-to-use-boric-acid-for-bv