〔Abstract〕 Objective To investigate the difference of clinical characteristics of recurrent spontaneous abortion(RSA) in patients with losses after spontaneous gestation and afterin vitrofertilization and embryo transfer(IVF-ET). Methods 237 patients diagnosed with RSA were divided into spontaneous gestation group(n=185) and IVF group(n=52) according to their previous modes of fertilization. The clinical characteristics of the two groups were analyzed. Results Compared with the spontaneous gestation group, the age of the first pregnancy and the age at the time of RSA in the IVF group were statistically greater than those in the natural pregnancy group(P<0.05). The number of biochemical pregnancies in IVF group was statistically higher than that in spontaneous gestation group, and the number of spontaneous abortions in IVF group was statistically lower than that in spontaneous gestation group(P<0.001). The proportion of patients with irregular menstruation in IVF group was statistically higher than that in spontaneous gestation group(P<0.05). The serum activated partial prothrombin time(APTT), R, K, high density lipoprotein cholesterol(HDL-C), thyrotropin(TSH) and homocysteine(HCY) in IVF group were statistically lower than those in spontaneous gestation group, and the Angel, Ma, low density lipoprotein cholesterol(LDL-C) and body mass index(BMI) in IVF group were statistically higher than those in spontaneous gestation group(P<0.05). In the comparison of etiological composition between the two groups, the proportion of anatomical factors in IVF group was statistically higher than that in spontaneous gestation group(P<0.05). Conclusion The abortion risk factors in RSA patients after IVF-ET is more serious than that in RSA patients after natural pregnancy. It is suggested to further improve and implement the pre-pregnancy examination and education of infertile patients during IVF-ET treatment, so as to reduce the risk of RSA and obtain a better pregnancy outcome.