Objective To explore the mechanism action of Shoutai Pill in the embryo from the molecular level.Methods The model of normal pregnancy was established with the model of recurrent abortion CBA/J ×DBA/2.The recurrent abortion model CBA/J×DBA/2 in pregnant mice were randomly divided into model group,high-,medium-,low-dose group of Shoutai Pill.From the first day of gestation,mice were given medicine by gavage for 14 d,and then sacrificed.Immunohistochemistry was used to detect differences in protein HSP27,α-enolase,transferrin,annexin A2 protein expression.Results Compared with normal group,decidual HSP27 and α-enolase expression of model group increased significantly,the expression of transferrin and annexin A2 was significantly decreased,with significant differences(P 0.01).Compared with model group,decidual HSP27 and α-enolase expression of Shoutai Pill high and low dose group decreased,annexin A2 expression was increased.Compared with model group,expression of decidual transferrin of Shoutai Pill high dose group increased,with significant differences(P 0.01),decidual transferrin expression of Shoutai Pill medium and low dose group had no significant difference(P 0.05).Conclusion Through the protein expression,Shoutai Pill achieves the maintenance of pregnancy,reducing the rate of embryo resorption,which may be one of the mechanisms of Shoutai Pill preventing miscarriage effect.