I would like to know what if any opinion there is regarding the procedure of hair transplant surgery. It is a cosmetic and not medical related surgery done to approve one’s appearance.
Halachic opinions differ over the permissibility of plastic surgery if there is even a minor medical risk attached to the procedure and if the benefits are purely aesthetic and “in the eyes of the beholder”. If on the other hand the cosmetic surgery is performed to correct an objective blemish, or if it is necessary so as to find a job or a suitable spouse it is permitted (Nishmat Avraham Yoreh Deah 155 b 3). Similarly, for a man, dyeing one’s hair (and a hair transplant would be in the same category) for aesthetic reasons alone is prohibited; it is included in the prohibition against a man dressing like a woman. Again, for economic or social reasons this too is permitted (Nishmat Avraham Yoreh Deah 182 b).