In general, low prolactin is not so much of a concern in either gender as prolactin is only used for breastfeeding.
However, if the doctor did not do complete testing on the pituitary hormones, it could show hypopituitary or panhypopituitary. Sadly, most endos only look for the most common pituitary tumor - prolactinoma - and not test the other hormones like ACTH, IGF-1, TSH, ADH, FSH and LH.
Signs of pituitary issues can be subtle or in your face - acne, fatigue, weird hair growth, headaches, lack of libido, weight loss or weight gain, and a bunch of others that can depend largely on the tumor or hormone.
The testing would be lab work and if there is further suspicion, a dynamic MRI of the pituitary.
Thanks for your valuable reply.Its really useful for me.
There is information in the health pages (below or trying to move to right) as well as feel free to ask.
I am panhypopituitary.