【摘要】 目的 探讨胚胎着床前遗传学检测(PGT)是否影响辅助生殖技术(ART)中单卵双胎(MZT)的发生率。方法 采用回顾性队列研究设计，纳入2014年1月至2022年12月在我院生殖中心行解冻单囊胚移植且获得临床妊娠的19 950个周期为研究对象。根据是否行PGT将周期分为PGT组(2 929个周期)和非PGT组(17 021个周期),采用囊胚滋养层细胞活检后冻存并行单囊胚解冻移植的周期纳入PGT组，囊胚培养后直接冻存行单囊胚解冻移植的周期纳入非PGT组。比较两组患者的流产率、新生儿低出生体重率，以及单卵双胎(MZT)发生率。结果 两组基线资料比较显示，PGT组的男、女方年龄显著小于非PGT组(P<0.01),卵胞浆内单精子注射(ICSI)比例、继发不孕率均显著高于非PGT组(P<0.01)。PGT组44个周期发生MZT,发生率为1.50%(44/2 929);非PGT组322个周期发生MZT,发生率为1.89%(322/17 021)。两组MZT发生率比较无显著性差异(P>0.05)。在妊娠结局方面，PGT组的总流产率显著低于非PGT组(12.80%vs. 19.13%,P<0.01),新生儿低出生体重率亦显著低于非PGT组(3.92%vs. 4.44%,P<0.01)。多因素Logistic回归进一步校正年龄、授精方式及不孕类型等因素后证实，PGT并非MZT发生的独立影响因素[OR=0.745,95%CI(0.52,1.07),P=0.108]。结论 基于囊胚滋养层细胞活检的PGT周期不增加MZT的发生风险。更多还原

【Abstract】 Objectives:To investigate whether preimplantation genetic testing(PGT) affects the incidence of monozygotic twinning(MZT) in assisted reproductive technology(ART).Methods:A retrospective cohort study was conducted among patients who achieved clinical pregnancy after thawed single blastocyst transfer at the Center for Reproductive Medicine in our hospital between January 2014 and December 2022. A total of 19 950 cycles were divided into PGT group(2 929 cycles) and non-PGT group(17 021 cycles). All PGT embryos underwent trophectoderm biopsy followed by cryopreservation, and non-PGT embryos were cryopreserved without biopsy. The miscarriage rate, low-birth-weight rate and MZT incidence were compared.Results:A comparison of baseline data between the two groups revealed that the male and female ages in the PGT group were significantly younger than those in the non-PGT group(P<0.01),while the rates of intracytoplasmic sperm injection(ICSI) and secondary infertility were significantly higher in the PGT group(P<0.01). In the PGT group, 44 cases of MZT occurred, with an incidence rate of 1.50%(44/2 929). In the non-PGT group, 322 cases of MZT occurred, with an incidence rate of 1.89%(322/17 021). There was no significant difference in the MZT incidence rates between the two groups(P>0.05). Regarding pregnancy outcomes, the overall miscarriage rate(12.80 % vs. 19.13%) and the low-birth-weight rate(3.92% vs. 4.44%) in the PGT group were significantly lower than those in the non-PGT group. Multivariate logistic regression further adjusted for factors such as age, the fertilization method and the infertility type, confirming that PGT was not an independent influencing factor for MZT [OR=0.745,95%CI(0.52,1.07),P=0.108].Conclusions:PGT with blastocyst trophectoderm biopsy does not increase the risk of MZT.更多还原