Haematocrit >50% is the most frequent testosterone-related
adverse event in clinical trials. In a meta-analysis of19 randomised controlled trials – including a total of 1084 subjects, 651 on testosterone, 433 on placebo – testosteronetreated men were nearly 4 times as likely as placebo-treated
men to develop a haematocrit >50%. The clinical significance of this increase is still unclear, but carefully monitoring of this parameter should be performed regularly