To summarize recent knowledge from experimental studies and randomized clinical trials in benign prostate hyperplasia that compare bipolar with monopolar transurethral resection, with an emphasis on morbidity. Bipolar transurethral resection of the prostate has a urodynamically proven efficacy to relieve bladder outlet obstruction, which seems to be durable in time with low long-term complication rates. The haemostatic capacity of bipolar current is shown to be superior in ex-vivo studies. Postoperative bleeding and blood transfusion rates are similar. Clot retention and transurethral resection syndrome rates are significantly lower in patients treated with bipolar resection. Catheterization time and length of hospital stay are statistically shorter for Gyrus but insignificant for the transurethral resection in a saline system compared with monopolar resection. Urethral stricture rates do not differ significantly between arms. Bipolar shares similar clinical efficacy with monopolar transurethral resection of the prostate, durable in time with low long-term complication rates. It has minimized bleeding risk and eliminated transurethral resection syndrome. The evidence derived from randomized clinical trials does not support a statistically significant incidence of urethral strictures with bipolar compared with monopolar current.