Effect of Tripterigium wilfordii Hook. f. on the fertility of rats.

Studies were undertaken to assess the effect of the total glycosides extracted from Tripterigium wilfordii Hook. f. (GTW), a ready-made Chinese herb medicine, on the fertility of both male and female rats. In male rats, GTW was given by gastric gavage at a dose of 10 mg/kg per day, 6 days a week for 8 weeks. All the treated animals became infertile. The body weight growth was normal and the mating behavior was present. There was a drastic decrease in the viability of the epididymal spermatozoa, while the decrease in the sperm density, though significant, was far less marked. Seminiferous tubular damage was minimal and no perceptible change was observed in the Leydig and the Sertoli cells. All other parameters examined, including the serum testosterone level and the histology of various organs, were normal. In female rats, GTW given orally at a dose of 50 mg/kg per day on days 1-4 or 7-9 of pregnancy did not significantly affect the fertility. It is thus concluded that non-toxic dose of GTW can cause infertility in male rats, the mechanism of which may involve and interference in the function of the epididymal and/or testicular spermatozoa; in female rats, the dose regimens employed do not have significant anti-implantation or early-pregnancy termination effect.