Abstract: Objective To observe the toxicity effect of arctigenin on rat fertility and early embryo development in SD rats. Methods SD rats were divided into solvent control group and arctigenin 4, 16, 64 mg?kg-1 three dose groups, 25 animals per sex per group. Prior to mating, male rats were treated 10 weeks and female rats were treated 2 weeks respectively by subcutaneous injection with volume 2 mL?kg-1 once a day. Within each treatment group, the male and female rats were co-housed (1:1) until evidence of mating was seen or for 2 consecutive weeks. During cohabitation period, total animals were continuously treated. After successful mating, female rats still were treated until day 6 of pregnancy and male rats were kept treating until euthanized. Clinical observations, body weights and food consumption were recorded routinely. Male rats were euthanized 1 week after successful mating, then sperm quality and reproductive organs were inspected; female rats were euthanized on day 15 of pregnancy, then the corpora luteum number, implantation number, viable fetuses number, absorbed fetuses number, dead fetuses number, uterus and ovary weight were inspected. Results During treating times, stimulation of drug delivery site were seen on all groups animals, arctigenin 16, 64 mg?kg-1 dose group caused 1 animal death respectively. Body weights and feed consumption in all arctigenin treatment groups were not significantly different when compared with the solvent group. There had no abnormal changes on animal precoital interval, mating index, gestation index, sperm quality of male rats and pregnancy outcome of female rats. Conclusion Under this experimental environment, arctigenin has no significant toxicity on rat fertility and early embryo development, and the no observed adverse effect level（NOAEL）is 64 mg?kg-1.

Key words: arctigenin, fertility, early embryo, implantation