To dispel your doubts, after undergoing a hair transplantation procedure there is one important possible precaution you need to take. And that is to sleep on your side, not flat on your back. This will prevent your head from moving too much and probably dislodge your newly transplanted grafts and aggravate the raw wound on the donor area. You could also protect your newly transplanted hair by arranging your pillow in a staggard upright position. The transition of your position although unnoticeable will greatly help protect your head from accidentally bumping on the headboard. This is another sleeping position that will also minimize rubbing your new hair grafts on your pillows.