Objective:To evaluate clinical efficacy and safety of immunotherapy by retrospectively analyzing clinical medica-tion of patients with recurrent pregnancy loss(RPL)complicated with abnormal immune factors.Methods:A retrospective cohort study was conducted on RPL cases in outpatient department of Hebei Reproductive Health Hospital from January 2021 to April 2022.Efficacy and safety of immunotherapy were evaluated from pregnancy outcome,adverse reactions and birth defects of offspring.Results:According to guidelines,192 cases with abnormal autoimmunity and/or immune indicators were included.Early abortion rate was 4.16%in group of two lost pregnancies,which was lower than that in group of three lost pregnancies(16.66%).Twelve week sus-tained pregnancy rate was 89.58%in the former group,and 28 week sustained pregnancy rate was 86.45%,which were significantly higher than those in the latter group(75.00%,71.87%).RPL patients were divided into groups according to their exposure to immuno-modulatory drugs before 12 weeks of pregnancy.There was no significant difference in pregnancy outcome,adverse reaction rate and birth defect rate of their offspring(P>0.05).Conclusion:Immunotherapy can effectively reduce risk of recurrent abortion and increase rate of persistent pregnancy in patients with immune RPL.Personalized immunotherapy can make RPL patients with immune factors achieve expected effect of fetal protection.