Not necessarily so -- only if that was the sole cause of the facial hair growth.

Remember that for many women it's normal for them to have facial hair. Normal in terms of the way that THEIR body functions. Normal in terms of the fact that their body was sensitized in early fetal life to respond to testosterone. Normal in terms of the fact that their body produces high levels of testosterone and/or lower than average levels of estrogen. Normal in terms of the fact that their body produces lower than average levels of SHBG to bind testosterone. All of these things may have nothing whatsoever to do with the pituitary gland, but may still result in moustache and beard growth similar to that which is normal for males.