Hair loss is primarily caused by a combination of aging, a change in hormones, and a family history of baldness. As a rule, the earlier hair loss begins, the more severe the baldness will become. Hair loss can also be caused by burns or trauma, in which case hair replacement surgery is considered a reconstructive treatment,

Hair transplantation involves removing small pieces of hair-bearing scalp grafts from a donor site and relocating them to a bald or thinning area. Grafts differ by size and shape. Round-shaped punch grafts usually contain about 10-15 hairs. The much smaller mini-graft contains about two to four hairs; and the micro-graft, one to two hairs. Slit grafts, which are inserted into slits created in the scalp, contain about four to10 hairs each; strip grafts are long and thin and contain 30-40 hairs.