RESUMEN
<p><b>OBJECTIVE</b>To study the anti-fertility effect of maximum-dose Tongbi Composition and its reversibility in male rats.</p><p><b>METHODS</b>Thirty-six male SD rats were equally randomized into a control group and a medication group, the former given normal saline at 10 ml/(kg x d), while the latter treated with Tongbi Composition at 10 g/(kg x d), both for 60 days. Half the rats of each group were sacrificed randomly at the cessation of treatment, and the rest killed at 72 days after it. The relative testis weight, testis volume, sperm concentration and sperm motility were measured, and the pathological changes in the testicular tissue observed under the optical microscope.</p><p><b>RESULTS</b>After 60 days of treatment, no statistically significant differences were found between the two groups in the relative testis weight, testis volume and sperm concentration (P > 0.05) , and the sperm motility of the medication group dropped to zero, but it was restored to normal at 72 days after drug withdrawal. Almost no lesions were observed in the testis tissue of the medication group.</p><p><b>CONCLUSION</b>The short-term use of Tongbi Composition at the maximum clinical dose has an obvious anti-fertility effect, but it is reversible.</p>