Bacterial vaginosis is best treated naturally by eliminating the root cause of BV – the changed vaginal acidity – and thus getting rid of it forever. At times, the vagina gets back its own level of acidity in due course of time, and that is when bacterial vaginosis does not tend to recur. But quite often this is not the case, and then the BV becomes recurring.
Lets explain in more detail. Suppose your vaginal pH (acidity) has changed and as a result you have caught BV. What would a traditional remedy system do? It would attempt to kill the bad bacteria that has grown due to the changed vaginal ambiance. And that is what metronidazole and the likes as well as over-the-counter (OTC) products tend to do – kill bacteria. The catch is that, these substances kill bacteria without distinguishing between good or bad, and your vagina houses good bacteria too. So for some time, the levels of both these kinds of bacteria dips. This would help in general reduction of bacterial infection in women rather than only helping control BV.
And while the quantity of the bacteria inside the vagina is still low – the effect of the conventional treatment is still on (usually that translates to “the immunity provided by the antibiotics/OTC is still high enough”) – if your vagina regains the desired levels of pH, you would be cured. And in that case, the cure would be permanent. In other words, the conditions will not recur.
In reality, quite often your vagina would not regain the desired acidity level on its own. And if that is the case, then once the effects of the treatment is gone, the bacterial vaginosis would come back. The reason is that your vagina is still measuring an undesired level of acidity, and the effects of your treatment (OTC etc) is no longer strong enough to kill the bacteria. So you would unfortunately come back to the same old situation and the symptoms and troubles would start showing up once again.
BV does get cured with traditional treatment, but there are too many exceptions. The above is how the exception happens, and happens often enough. Hence, both the schools of treatments for bacterial vaginosis exist in parallel.