Aims: As a medical herb, Capparis spinosa is used in the traditional medicine. Nevertheless, its side-effects are not yet studied, especially during the pregnancy. The aim of this study was to investigate the tratogenic effects of hydro-alcoholic extract of the leaves of Capparis spinosa on the embryo of Balb/c mice.

Materials & Methods: In the experimental method, 32 pregnant Balb/c mice were randomly divided into four groups including control and experimental groups. The experimental groups were the groups received 200, 400, and 800mg/kg hydro-alcoholic extract doses of the leaves of Capparis spinosa. Experimental and control groups received the extract doses and urban water as 14-day gavage, respectively. The 18-day embryos, removed out of the uterus by Cesarean, were investigated in the physical deformations. Alizarin staining method was used to assess the embryonic skeletal system. Data was analyzed using one-way ANOVA and Newman-Keuls method.      

Findings: There was a significant reduction in the mean weight of the pregnant mice at the 18^th day of pregnancy in 800mg/kg extract group compared to control group (p<0.05). In addition, there were significant reductions in the mean height and weight of the embryos of the mice in 800mg/kg extract group than control group (p<0.05). There was no embryonic physical and skeletal deformation in the experimental groups. 

Conclusion: 800mg/kg hydro-alcoholic extract of the leaves of Capparis spinosa affect height and weight of the embryos of Balb/c mice and might have tratogenic effects on embryo.