Is there a treatment to grow back hair on vagina?

Many drugs have hair loss as a side effect. However, in most cases the use of drugs are not the primary cause.  

If your hair loss was due to kidney disease and if was reversible, it may take up to one full year to see hair grow back.  However it probably isn't as simple as one direct cause.  There are many people with kidney disease who have a full head of hair.

Having orgasm or having sex does not cause hair loss. Even if it does, would you consider being asexual?  Your genetic predisposition causes male pattern balding.  

You can be a smarter consumer if you understand there is no cure for genetic hair loss.  Even Propecia does not stop or cure genetic male pattern hair loss.  You can try alternative treatments but it is unclear why you think green tea and soybeans would help.

There is no way to "test" if your hair follicles are active. One obvious way to tell is if you see hairs grow.  If you notice no hair growth for 6 to 12 months then it probably is a "dead" follicle.Hair loss due to stress will be diffuse.  Hair loss due to DHT from genetic male...

You won't be able to tell if your hair loss is permanent. Only way is to wait to see if the hairs grow back.  It may take up to one year.