Results of laser hair removal vary greatly from person to person. Multiple treatments can prolong the duration of hair loss, but hair regrowth is still possible. For best results, you may need four to six treatments spaced a number of weeks apart. Additional periodic maintenance treatments — perhaps once every six to 12 months — may be needed as well.
Some conditions can accelerate hair regrowth such as puberty, pregnancy, menopause, etc. It isn't necessarily that the hair grows back, but new hairs begin to grow.