ABSTRACT
OBJECTIVE: To compare the pregnancy outcomes between the spontaneous reduction in twin pregnancy and the singleton pregnancy after assisted reproductive technology(ART).METHODS: A total of 121 cases of spontaneous reduction in twin pregnancy,who received ART at the Reproductive Center of Peking University First Hospital from January 1,2008 to December 31,2017,were included in the study,and were divided into early and middle spontaneous reduction groups with 95 and 26 cases in each group.Simultaneously,320 women with a singleton pregnancy were recruited as controls.Characteristics compared included the general condition of pregnant women,preterm birth as well as obstetric pregnancy outcomes.RESULTS: The overall birth weight in middle spontaneous reduction group was lower than that in early spontaneous reduction group and control group[(2361.54±724.07)g,(3144.42±506.73)g,(3332.23±493.32)g](P0.05).CONCLUSION: Spontaneous reduction under ART is associated with lower birth weight and higher incidence of premature delivery,whereas middle spontaneous reduction is associated with increased adverse pregnancy outcomes.