Figure 2: Dose-dependent effect of FSH therapy on sperm concentration and total count. Treatment with FSH improved the (a) sperm concentration and (b) total sperm count in men with idiopathic oligozoospermia compared with controls. (a) At low doses, FSH therapy did not ameliorate the sperm concentration; at intermediate and high doses, FSH administration increased the sperm concentration in a dose-dependent manner. (b) At low doses, FSH did not improve the total sperm count; at intermediate doses, the total sperm count showed a trend toward the increase; and at high doses, FSH ameliorated the total sperm count. FSH: follicle-stimulating hormone; CI: confidence interval; s.d.: standard deviation; a–d: study subgroups; IV: Inverse Variance methods; df: degree of freedom.