Objective To investigate the efficacy of low molecular weight Heparin Sodium in the treatment of recurrent abortion.Methods A total of 60 patients with recurrent abortion admitted to Xinyu Maternal and Child Health Hospital from December 2019 to April 2021 were selected as the research objects.According to the random number table method,they were divided into control group and observation group,with 30 cases in each group.Control group was treated with Didroxyprogesterone combined with Phloroglucinol.Observation group was treated with subcutaneous injection of low molecular weight Heparin Sodium on the basis of the control group.The pregnancy outcome,sex hormone level and pregnancy complications were compared between the two groups.Results The live birth rate and the rate of ectopic gestation of the observation group were higher than those of the control group,the abortion rate,the rate of fetal death in the observation group were lower than those in the control group,the differences were statistically significant (P＜0.05).There were no significant differences in the levels of human chorionic gonadotropin (HCG),progesterone (P)and estradiol (E2)between the two groups before intervention (P＞0.05).After treatment,the levels of HCG,P and E2 in the two groups were higher than those before intervention,and the levels of HCG,P and E2 in the observation group were higher than those in the control group,the differences were statistically significant(P＜0.05).The total incidence of pregnancy complications in the observation group was lower than that in the control group,the difference was statistically significant(P＜0.05).Conclusion Low molecular weight Heparin Sodium is effective in the treatment of recurrent abortion.It can improve the live birth rate,improve the levels of HCG,P and E2,and reduce the incidence of pregnancy complications.