冻融周期薄型子宫内膜移植胚胎类型对临床结局的影响

Effect of the types of transferred embryo on clinical outcomes of frozen-thawed embryo transfer among patients with thin endometrium

目的探讨可以改善薄型子宫内膜患者助孕结局的胚胎移植策略。方法采用回顾性队列研究分析2013年1月至2019年12月期间于河南省人民医院生殖医学中心行冻融胚胎移植的1924例薄型子宫内膜患者共2452个周期的临床资料。根据移植胚胎的类型分为移植卵裂期胚胎(卵裂胚组)和移植囊胚期胚胎(囊胚组),通过单因素分析、多因素logistic回归分析及曲线拟合对比卵裂胚和囊胚周期的临床结局。结果卵裂胚组移植2枚胚胎周期占比[87.17%(1298/1489)]、异位妊娠率[3.35%(16/477)]及多胎分娩率[23.32%(73/313)]高于囊胚组[40.71%(392/963),P<0.001;0.76%(4/524),P=0.003;16.27%(55/338),P=0.024];囊胚组临床妊娠率[54.41%(524/963)]及活产率[35.10%(338/963)]显著高于卵裂胚组[32.03%(477/1489),P<0.001;21.02%(313/1489),P<0.001];多因素logistic回归分析结果显示,调整混杂因素对临床结局的影响后,囊胚组的临床妊娠率(OR=3.42,95%CI=2.71~4.31,P<0.001)及活产率(OR=2.35,95%CI=1.84~3.00,P<0.001)高于卵裂胚组;分层分析结果显示,不同内膜厚度分层中囊胚组的临床妊娠率(<6 mm:OR=2.94,95%CI=1.32~6.51,P=0.008;6~7 mm:OR=3.41,95%CI=2.13~5.45,P<0.001;>7 mm:OR=3.56,95%CI=2.67~4.74,P<0.001)和活产率(<6 mm:OR=2.50,95%CI=1.01~6.22,P=0.049;6~7 mm:OR=2.56,95%CI=1.56~4.21,P<0.001;>7 mm:OR=2.30,95%CI=1.71~3.10,P<0.001)均高于卵裂胚组。分层曲线拟合分析结果显示,两组的临床妊娠率和活产率均随子宫内膜厚度的增加而增加,任一子宫内膜厚度下囊胚组的临床妊娠率与活产率均高于卵裂胚组,且与囊胚组相比,卵裂胚组内膜厚度与临床妊娠率曲线拟合的斜率更大。结论薄型子宫内膜患者冻融胚胎移植周期中囊胚移植周期的临床妊娠率和活产率均高于卵裂胚移植周期。孕酮转化日子宫内膜厚度的增加可以改善薄型子宫内膜患者的临床妊娠率和活产率。

Objective To explore the clinical strategies to improve the clinical outcomes of patients with thin endometrium.Methods A retrospective cohort study was conducted to analyze 1924 frozen-thawed embryo transfer(FET)cycles of 2452 patients with thin endometrium at the Reproductive Medicine Center of Henan Provincial People's Hospital from January 2013 to December 2019.According to the type of embryos transferred,they were divided into the embryo group at cleavage stage(cleavage embryo group)and embryo group at blastocyst stage(blastocyst group).Univariate analysis,multivariate regression analysis,curve fitting and threshold effect analysis were used to compare the clinical outcomes of the cycles transferring cleavage stage embryo and blastocyst.Results The percentage of cycles with two embryos transferred[87.17%(1298/1489)],the rate of ectopic pregnancy[3.35%(16/477)]and the rate of multiple births[23.32%(73/313)]in cleavage embryo transfer cycle were higher than those of blastocyst transfer cycle[40.71%(392/963),P<0.001;0.76%(4/524),P=0.003;16.27%(55/338),P=0.024].The clinical pregnancy rate[54.41%(524/963)]and the live birth rate[35.10%(338/963)]in blastocyst transfer cycle were significantly higher than those of cleavage embryo transfer cycle[32.03%(477/1489),P<0.001;21.02%(313/1489),P<0.001].After adjusting for confounders,the clinical pregnancy rate(OR=3.42,95%CI=2.71-4.31,P<0.001)and the live birth rate(OR=2.35,95%CI=1.84-3.00,P<0.001)of blastocyst transfer cycle were higher than those of cleavage stage embryo transfer cycle.The results of stratified analysis showed that the clinical pregnancy rate(<6 mm:OR=2.94,95%CI=1.32-6.51,P=0.008;6-7 mm:OR=3.41;95%CI=2.13-5.45,P<0.001;>7 mm:OR=3.56,95%CI=2.67-4.74,P<0.001)and the live birth rate(<6 mm:OR=2.50,95%CI=1.01-6.22,P=0.049;6-7 mm:OR=2.56,95%CI=1.56-4.21,P<0.001;>7 mm:OR=2.30,95%CI=1.71-3.10,P<0.001)of blastocyst transfer cycle in different endometrial thickness stratifications were higher than those of cleavage stage embryo transfer cycle.The results of stratified curve fitting analysis showed that with increasing endometrial thickness among patients with thin endometrium,the clinical pregnancy rate and the live birth rate of both cleavage stage embryo cycle and blastocyst transfer cycle increased,and in all of the different endometrial thickness stratifications,the clinical pregnancy rate and the live birth rate in blastocyst transfer cycle were higher than those of cleavage embryo transfer cycle.Compared with the blastocyst transfer cycle,the slope of curve fitting between endometrial thickness and clinical pregnancy rate was larger in cleavage embryo transfer cycle.Conclusion The clinical pregnancy rate and the live birth rate of the blastocyst transfer cycle in FET were higher than those of cleavage stage embryo transfer cycle.The increasement of endometrial thickness on the first day of progesterone administration can improve the clinical pregnancy rate and the live birth rate in patients with thin endometrium.