生殖医学杂志

目的 探讨通过胚胎形态学观察进行选择性卵裂期单胚胎移植策略优化的应用价值。方法 回顾性分析2019年6月至2020年10月在苏州市立医院生殖与遗传中心行IVF/ICSI-ET卵裂期胚胎新鲜周期移植或全胚冷冻保存后第1个冻融卵裂期胚胎移植患者的临床资料。根据患者是否进行受精后第2天(D2)胚胎形态学观察和胚胎移植数目分为：D2、D3连续观察卵裂期单胚胎移植组(连续观察单胚组)70个周期；无D2观察、仅D3观察卵裂期单胚胎移植组(D3观察单胚组)97个周期；仅D3观察卵裂期双胚胎移植组(D3观察DET组)564个周期。比较3组患者的一般资料、促排卵及胚胎发育实验室指标、临床妊娠率、种植率、异位妊娠率和早期自然流产率等，并采用多因素Logistic回归分析临床妊娠率的影响因素。结果 3组患者的年龄、体质量指数(BMI)、基础性激素水平、基础窦卵泡计数(AFC)等比较均无显著性差异(P>0.05)。3组患者的不同受精方式占比、Gn总量、HCG日内膜厚度、HCG日P水平、刺激天数均无显著性差异(P>0.05)。D3观察单胚组的获卵总数、成熟卵子数、2PN受精数、卵裂数、优胚数、成囊胚数显著低于其他两组(P<0.05),D3观察单胚组的临床妊娠率、HCG阳性率亦显著低于其他两组(P<0.05),连续观察单胚组的种植率显著高于其他两组(P<0.05);3组间的异位妊娠率、早期流产率无显著性差异(P>0.05)。连续观察单胚组和D3观察单胚组均无多胎妊娠发生，D3观察DET组的多胎妊娠率为42.37%(161/380)。采用多因素Logistic回归分析抗苗勒管激素(AMH)、HCG日E₂水平、促排卵方案、获卵数、2PN受精数等对临床妊娠率的影响，结果显示各因素对临床妊娠率均无显著影响(P>0.05)。结论 对于年龄<35岁、卵巢储备功能正常的患者，进行D2、D3连续胚胎形态学观察后选择发育潜能最佳的胚胎行卵裂期单胚胎移植可以获得较理想的临床妊娠率，降低多胎妊娠率。

Objective:To explore the application value of the optimal strategy for elective cleavage-stage single embryo transfer(SET) by the morphological observation.Methods:The clinical data of the first frozen-thawed embryo transfer after fresh cleavage-stage embryo transfer or whole embryo cryopreservation in the Center for Reproduction and Genetics, Suzhou Municipal Hospital from June 2019 to October 2020 were retrospectively analyzed. According to whether the embryo morphology was observed on the second day after fertilization(Day 2) and the number of embryos transferred, the IVF/ICSI-ET cycles were divided into three groups: Day 2 and Day 3 continuous morphological observation of SET group(continuous observation SET group, 70 cycles),no Day 2 observation, only Day 3 observation of SET group(Day 3 observation SET group, 97 cycles)and only Day 3 observation of double embryo transfer(DET) group(D3 observation DET group, 564 cycles). The general data, laboratory indicators of ovulation induction and embryonic development, clinical pregnancy rate, implantation rate, ectopic pregnancy rate and early miscarriage rate were compared among the three groups, and multivariate logistic regression was used to analyze the influencing factors of clinical pregnancy rate.Results:There were no significant differences in age, body mass index(BMI),basal sex hormone levels, and basal antral follicle count(AFC) among the three groups(P>0.05). There were no significant differences in the proportion of different fertilization methods, total dosage of Gn, endometrial thickness on HCG day, progesterone level on HCG day and stimulation days among the three groups(P>0.05). The numbers of oocytes retrieved, mature oocytes, 2 PN embryos, embryo cleavage, excellent embryos, and blastocyst formation in Day 3 observation SET group were significantly lower than those in the other two groups(P<0.05). The clinical pregnancy rate and HCG positive rate of Day 3 observation SET group were significantly lower than those of other groups(P<0.05). The implantation rate in continuous observation SET group was significantly higher than that of other groups(P<0.05). There was no significant difference in the rates of ectopic pregnancy and early miscarriage among the three groups(P>0.05). There was no multiple pregnancy in the continuous observation SET group and Day 3 observation SET group, and the multiple pregnancy rate in the Day 3 observation DET group was 42.37%(161/380). Multivariate logistic regression was used to analyze the effects of AMH,E₂ levels on HCG Day, ovulation stimulation protocol, number of oocytes retrieved, number of 2 PN embryos, and clinical pregnancy rate. The results showed that each factor above had no significant effect on clinical pregnancy rate(P>0.05).Conclusions:For patients younger than 35 years old with good ovarian reserve, through Day 2 and Day 3 continuous embryo morphological observation, selecting the cleavage stage embryo with the best developmental potential for single embryo transfer can obtain an ideal clinical pregnancy rate and reduce the multiple pregnancy rate.