Abstract: Objective: To explore the pregnancy outcomes after the reduction of triple pregnancies with monozygotic twins (MZT). Methods：A total of 47 cases of transvaginal reduction due to monozygotic（MZ）-triplets and 45 cases of transvaginal reduction due to non-MZ triplets in our Reproductive Center from January 2009 to December 2018 were retrospectively analyzed. The live birth rate， term birth rate， premature birth rate， early abortion rate， late abortion rate， the rate of the survival of one baby， the rate of the survival of two babies， gestational week of birth， neonatal birth weight and the incidence of low birth weight were compared between the two groups. Results：（1）The rate of premature birth and the rate of survival of two babies were decreased in the MZ-triplet group when compared with the non-MZ triplet group, and the rate of survival of one baby was increased（all P＜0.05）. （2） In 47 cases of MZ-triplet group， 16 cases were performed the embryonic reduction of single-egg single-embryo, and 31 cases were performed the embryonic reduction of one of MZ-twins embryos. Compared with 16 cases of the embryonic reduction of single-egg single-embryo， the rate of the survival of one baby and neonatal birth weight in 31 cases of the embryonic reduction of one embryo MZ-twins embryos were increased, while the incidences of the survival of two babies and low birth weight infant were decreased（all P＜ 0.05）. Conclusions：Transvaginal reduction of one of MZ-twins embryos in those triple-pregnancies with MZT is feasible and easier to obtain the outcome of single pregnancy.

Key words: Twins, monozygotic；, Pregnancy reduction, multifetal；, Pregnancy, triplet；, Pregnancy outcome；, Vagina