Sensitive areas with thin skin, such as the armpits and the bikini area, are much responsive to laser treatment than areas with thick skin, such as the back or chin. Hence, the percentage of hairs removed during one session will be much higher for thinner-skinned areas. Laser hair removal is a slightly long process. In order to remove unwanted hair completely from various areas of your body you will have to have the treatment repeated every 4 to 8 weeks, depending on the growing cycle of the hair. Permanent hair growth reduction can be achieved after at least 3 treatments, and occasional touch-up treatments may be necessary in order to maintain the optimal results.