低等级囊胚与不同质量分裂胚冻融后妊娠结局的比较

Comparison of clinical outcomes of vitrified low grade blastocysts and cleavage stage embryos with different quality

目的比较冻胚移植周期低等级囊胚与不同质量分裂胚冻融移植后的妊娠结局,探讨不同时期和质量的胚胎的发育潜能,为临床冻融周期移植胚胎的选择策略提供参考。方法回顾性分析2015年1月至2016年6月冻胚移植周期患者临床资料,将同一新鲜周期中既有第三天冷冻分裂胚又在第五天仅有低等级囊胚冷冻者纳入研究。其中冷冻的分裂胚按照形态学评分标准分为顶级冷冻分裂胚和次级冷冻分裂胚。患者自愿选择分裂胚或第5天囊胚解冻,移植2枚胚胎。移植胚胎均为低等级囊胚者243周期,移植胚胎均为顶级分裂胚者156周期,移植胚胎均为次级分裂胚者114周期。比较三组胚胎的临床妊娠率、种植率、早期流产率和多胎率,进行统计学分析。结果顶级分裂胚与低等级囊胚的临床妊娠率和种植率相似(64.20%vs.64.74%,44.03%vs.46.79%),显著高于次级分裂胚(49.12%,35.48%);顶级分裂胚的早期流产率显著低于低等级囊胚和次级分裂胚(3.96%vs.8.33%,7.14%);多胎率方面,顶级分裂胚最高(44.55%),其次为低等级囊胚(37.18%)和次级分裂胚(32.46%),但流产率和多胎率的差异无统计学意义。结论冻胚移植周期中,顶级分裂胚与低等级囊胚相比,具有更好的妊娠结局,次级分裂胚的临床结局较差。当患者冷冻的囊胚只有低等级,而同时有分裂胚冷冻时,首选顶级分裂胚进行解冻和移植,其次为囊胚,最后为次级分裂胚。

Objective To compare the clinical outcomes of vitrified low grade blastocysts and cleavage stage embryos with different quality and provide evidence for the choice of embryos to transfer in frozen-thawed embryo transfer（FET） cycles.Methods The clinical data of FET cycles from January 2015 to June 2016 were analyzed retrospectively.If the patients had both cleavage stage embryos vitrified on D3 and only low grade blastocysts vitrified on D5,their FET cycles were included.The cleavage stage embryos were divided into top quality group and non-top quality group according to their quality.The patients chose which kind of embryos to be thawed by their free will and were transferred two embryos.The clinical pregnancy rates,implantation rates,early miscarriage rates,and multiple pregnancy rates were compared between low grade D5 group（n=243）,top quality D3 group（n=156） and non-top quality D3 group（n = 114）.Results The clinical pregnancy rates and implantation rates were similar in low grade D5 group and top quality D3 group（64.20% vs.64.74%,44.03% vs.46.79%）,which were significantly higher than those in non-top quality D3 group.The early miscarriage rate in top quality D3 group was the lowest in the three groups（3.96% in top quality D3 group,8.33% in low grade D5 group and 7.14% in non-top quality D3 group）.Early miscarriage rates and Multiple pregnancy rates have no significantly different in the three groups（44.55% in top quality D3 group,37.18% in low grade D5 group and 32.46% in non-top quality D3 group）.Conclusion The top quality cleavage stage embryos achieved better clinical outcomes than low grade blastocysts.When the patients have only low grade blastocysts vitrified on D5,besides cleavage stage embryos vitrified on D3,top quality cleavage stage embryos are preferred to be thawed and transferred in their FET cycles.Blastocysts are the second choice,and non-top quality cleavage stage embryos are the last one.