冻融胚胎移植周期最佳胚胎移植策略的研究

Study of the best embryo transfer strategy in frozen-thawed embryo transfer cycle

目的通过分析冻融胚胎移植周期移植胚胎数量、质量与临床妊娠率和多胎妊娠率之间的关系探讨冻融胚胎移植周期最佳胚胎移植策略。方法回顾性分析冻融胚胎移植周期995例次的临床资料，以年龄35岁分层分析移植不同数量胚胎、优质胚胎周期之间的临床妊娠率和多胎妊娠率的差异。结果（1）年龄〈35岁患者，移植1、2、3枚胚胎组的临床妊娠率分别为50．0％、56．6％、56．5％，双胎妊娠率分别为6．3％、43．8％、30．6％，各组间临床妊娠率差异均无统计学意义（均P〉0．05），移植1枚胚胎组的双胎妊娠率显著低于其他两组（P〈0．05）；移植单个优质胚胎组的临床妊娠率与其他含优质胚胎移植组相似，多胎妊娠率低于其他组。（2）年龄i〉35岁患者，移植1、2、3枚胚胎组的临床妊娠率分别为0、47．3％、53．8％，双胎妊娠率分别为0、25．7％、25．7％，移植2枚和3枚胚胎组组间临床妊娠率、双胎率差异均无统计学意义（均P〉0．05）；移植2枚胚胎其中含1枚优质胚胎组临床妊娠率与其他移植不同数目优质胚胎组相似，多胎妊娠率低于其他组。结论移植胚胎数量、质量与冻融胚胎移植周期的临床妊娠率和多胎妊娠率之间关系密切；年龄〈35岁患者建议施行单个优质胚胎移植以降低多胎妊娠率；年龄≥35岁患者建议移植2枚胚胎其中含有1枚优质胚胎，以获得满意的临床妊娠率和较低的多胎妊娠率。

Objectives To study the relationship of the number and quality of embryos transferred with clinical pregnancy rate and multiple pregnancy rate in frozen-thawed embryo transfer （FET） cycle. Methods Retrospective analysis of the clinical data of 995 FET cycles. Patients were stratified as age 〈 35 or I〉35, Both groups＇ clinical pregnancy rate and multiple pregnancy rate were compared according to the number of embryos and high-quality embryos transferred. Results （ 1 ） The clinical pregnancy rates were 50. 0%, 56. 6% and 56. 5%, and twin pregnancy rates were 6.3%, 43.8% and 30. 6% respectively in 〈 35 group when one, two or three embryos were transferred. There is not any significantly statistic difference among these subgroups （P 〉 0. 05 ）. However, the twin pregnancy rate in one-embryo transferred subgroup was significantly lower than that of two-embryo transferred subgroup （ P 〈 0. 05 ）. Moreover, the clinical pregnancy rate was not different among single high-quality embryo transferred subgroup and other high-quality embryo transferred subgroups, the multiple pregnancy rate was lower than the others. （2）The clinical pregnancy rates were 0, 47. 3% and 53.8%, and twin pregnancy rates were 0, 25.7% and 25.7% respectively in ≥35 group when one, two or three embryos were transferred. The clinical pregnancy rate and twin pregnancy rate between two-embryo and three-embryo transferred subgroups were not significantly different （P 〉0. 05）. Moreover, the clinical pregnancy rate was not different among two-embryo transferred containing one high-quality embryo subgroup and other high-quality embryo transferred subgroups, the multiple pregnancy rate was lower than the others. Conclusions There is a close relationship between the number and quality of embryos transferred and clinical pregnancy rate, multiple pregnancy rate in FET cycles. For the patient aged 〈 35, we recommend performing single high-quality embryo transfer in order to reduce the multiple pregnancy. For the patient aged ≥35, two-embryo transfer containing one high-quality embryo is enough to obtain a satisfied clinical pregnancy rate and an acceptable multiple pregnancy rate.