A Cochrane review «Laser and photoepilation for unwanted hair growth»1 «Haedersdal M, Gøtzsche PC. Laser and photoepilation for unwanted hair growth. Cochrane Database Syst Rev 2006 Oct 18;(4):CD004684. »1 included 11 trials involving a total of 444 people. There appeared to be a short-term effect of approximately 50% hair reduction with alexandrite and diode lasers up to six months after treatment, whereas little evidence was obtained for an effect of intense pulsed light, neodymium:YAG or ruby lasers. Long-term hair removal was not documented with any treatment. Pain, skin redness, swelling, burned hairs and pigmentary changes were infrequently reported adverse effects.
A hospital-based comparative, observational prospective study «Nabi N, Bhat YJ, Dar UK, et al. Comparative study of the clinico-trichoscopic response to treatment of hirsutism with long pulsed (1064 nm) Nd:YAG laser in idiopathic hirsutism and polycystic ovarian »2 was carried out on female patients with hirsutism over a period of 18 months with 2 groups of participants: with idiopathic hirsutism (n=50) and with PCOS (n=50). Laser hair reduction was done with long pulsed (1064 nm) Nd:YAG laser in both groups up to 6 sessions, 4 weeks apart and followed for 3 months post last laser session. Excellent response (> 75% reduction, both clinically and trichoscopically with decrease in hair shaft thickness, hair shaft colour, terminal vs. vellus hair ratio and hair density per cm2) from baseline was seen in 70% of patients in idiopathic hirsutism and in 54% of patients in PCOS group. After 3 months of follow-up of the last laser session, the results persisted better in patients with idiopathic cause than in those due to PCOS.
Comment: The quality of evidence is downgraded by inconsistency (heterogeneity in interventions and outcomes), by indirectness (differences in studied patients), and by imprecise results (limited study size for each comparison).