Recipient-Site Influence in Hair Transplantation

In 2009, researchers conducted a study on a male patient with pattern baldness to examine the influence of the recipient site in hair transplantation. They transplanted nine chest hairs and occipital scalp hairs to the patient's scalp and observed them for one year. The transplanted chest hairs demonstrated a significant increase in length (56.3 mm compared to the original 28.5 mm) and a slight but significant increase in growth rate (10.4 mm/4 weeks compared to 8.9 mm/4 weeks). However, there was no significant change in hair thickness. These findings indicate that while the recipient site can significantly affect the growth rate and length of transplanted hairs, it does not alter their thickness, challenging the concept of donor dominance and highlighting the importance of the recipient site's environment on transplanted hair follicles' behavior.