Retention of fetal membranes （Retained Fetal Membranes,RFM）in dairy cow can lead to adverse health effects that ultimately affect ranch revenue. While the mechanisms behind of factors that caused RFM are not completely understood,the knowledge of the placental anatomy and physiology of placenta expulsion is helpful to manage this disease. This review discussed the physiology of placenta,the metabolism characteristics of transition period and the postpartum immunosuppression to better understand the process of detachment and etiology,pathogenesis and prevention. To uncover the cost of RFM,the study also analyzed various parameters resulting in economic losses in dairy herds.

dairy cow  /  retained fetal membranes（RFM）  /  transition period metabolism  /  immunosuppression