Assume one has a successful transplant. Is it possible for some of the yielded grafts to die or be rejected some time (even years) after the operation? I am not talking about hair loss, nor about grafts that are genetically doomed. I am talking about healthy grafts, from a safe zone, that are transplanted and bloom normally but after some time die. If it is possible what would the chances be and why would it happen?
If the transplanted hair grafts have successfully taken and have grown hair, they should last as long as the hairs from the donor area. Over many years some donor hairs may eventually fall out and die (senile alopecia) or experience a temporary hair loss (telogen effluvium/ stress related hair loss). If something like that would occur, then the transplanted hair will experience this same fate.
With respect to graft rejection, it is highly unlikely to happen since the transplanted hairs are your own (autologous graft). Your body will not reject the material from your own body in normal circumstances. Over the past 22 years, I have seen a few patients that reported loss of donor hair at about 5 years post transplant. I have no explanation for this, but the incidence is far less than 1% in my estimate.