不同胚胎移植策略对体外受精临床结局的影响

目的：比较人类胚胎体外培养第3天4种胚胎移植策略的临床结局。方法：回顾性分析了本中心2010年1月—2012年12月收治的≤35岁患者的第3天胚胎移植周期，均为第一次促排卵周期，采用控制性促排卵长方案和短方案，排除供精周期和遗传性疾病患者，获卵数≥2个。根据移植胚胎数及评分（评为Ⅰ、Ⅱ、Ⅲ、Ⅳ级，Ⅰ、Ⅱ级为高评分胚胎，Ⅲ、Ⅳ级为低评分胚胎）分为4组：A组移植1枚高评分胚胎，B组移植2枚高评分胚胎，C组移植1枚高评分胚胎和1枚低评分胚胎，D组移植2枚低评分胚胎。比较4组的临床妊娠率、胚胎着床率、双胎率、流产率和活产率。结果：4组的流产率分别为8.67%、10.34%、13.54%、20.00%，差异无统计学意义（χ2=4.146，P=0.246）；B组的每周期临床妊娠率和活产率分别为55.94%、49.38%，均高于A组（32.05%、28.63%）和C组（42.86%、37.72%），差异有统计学意义（P＜0.000 1），C组的每周期临床妊娠率和活产率高于A组，差异有统计学意义（P＜0.01）；然而，B组的双胎率（36.31%）高于A组（0.67%）和C组（27.60%），差异有统计学意义（P＜0.01）。结论：选择1枚高评分胚胎与1枚低评分胚胎协同移植，可获得可接受的每周期临床妊娠率和活产率，亦未提高双胎率。

Clinical Outcomes of Different Embryo Transfer Strategies in IVF Treatment Cycles

Objective: To compare the clinical outcomes of different strategies of embryo-transfer (ET) on the day 3 of in vitro cultured embryos in IVF treatment cycles. Methods：This is a retrospective study on those ET cycles on the day 3 of in vitro cultured embryos in those patients aged lower than or equal to 35 years in our IVF center from January 2010 to December 2012. All cycles were the first stimulated ovulation induced by long and short programs. The sperm-donor cycles and the genetic diseases cycles were excluded. Ocytes in every cycle were more than or equal to two. The strategies of ET were divided into four groups, based on the embryo number of ET and the embryo score（embryos were scored asⅠ, Ⅱ, Ⅲ, Ⅳ; while Ⅰ and Ⅱ were considered as high-score embryos and Ⅲ and Ⅳ as low-score embryos）. Group A, transfer one high-score embryo; Group B, transfer two high-score embryos; Group C, transfer one high-score embryo and one low-score embryo; and Group D, transfer two low-score embryos. The rates of clinical pregnancy, implantation, twin pregnancy, miscarriage and live birth among 4 groups were compared. Results：There was not significant difference in the miscarriage rates among four groups （8.67%, 10.34%, 13.54%, 20.00%; χ2=4.146，P=0.246）. The rates of clinical pregnancy and live birth per ET cycle in the group B（55.94%, 49.38%） were significantly higher than those in the group A （32.05%、28.63%） and the group C（42.86%, 37.72%）, respectively（P＜0.000 1）. The rates of clinical pregnancy and live birth per ET cycle in the group C were significantly higher than those in the group A（P＜0.01）． However, the rate of twin pregnancy in the group B（３６．３１％） was significantly higher than those in the group A（０．６７％） ａｎｄ ｔｈｅ ｇｒｏｕｐ Ｃ（２３．９６％）（Ｐ＜０．０１）． Conclusions：The strategy of ET of one high-score embryo combined with one low-score embryo can get acceptable rates of clinical pregnancy and live birth per ET cycle, while it does not increase the rate of twin pregnancy.