[Analysis of clinical factors on early pregnancy loss during in vitro fertilization-embryo transfer treatment and natural pregnancy].

Objective: To compare differences of clinical factors related to early pregnancy loss between invitro fertilization-embryo transfer (IVF-ET) treatment and natural pegnancy. Methods: A retrospective analysis was performed on the 363 cases of early pregnancy loss between Dec. 2015 to May 2016 in Peking University Third Hospital, during which 173 cases were after IVF-ET treatment (IVF-ET group) , and others were natural pregnancies (natural group) . Results: The average age in IVF-ET group was significantly higher than that in the natural group [ (34.1±4.3) versus (31.8±4.1) years old, P<0.01]. The terminating time of pregnancy loss in IVF-ET group was short than that in the natural group [ (59.8±9.2) versus (69.9±11.1) days, P<0.01]. The incidence of embryo abnormal chromosome in IVF-ET group was significantly lower than that in the natural group [57.2% (99/173) versus 74.2% (141/190) , P<0.01], during which abnormal chromosome numbers were the most common. Conclusions: The pregnancy loss of early pregnancy is mainly caused by chromosome abnormality. The proportion of chromosome abnormality in early pregnancy loss after IVF-ET is not higher than that of natural pregnancy, indicating that there are relatively reliable gametes and embryo safety in IVF treatment.