探讨同一促排卵周期全胚冷冻患者，冻融胚胎移植(FET)次数与临床妊娠率的关系。

选择2012年1月至2016年9月在苏北人民医院生殖医学中心实施全胚冷冻后FET的807例患者为研究对象，按照FET累计次数不同，将FET累计1次者纳入A组(n＝543)，FET累计2次者纳入B组(n＝181)，FET累计3次者纳入C组(n＝63)，FET累计4次者纳入D组(n＝20)。回顾性分析807例患者的一般临床资料、移植周期资料以及累计临床妊娠率、临床妊娠率。

①4组患者的年龄、不孕年限、人体质量指数(BMI)、不孕类型构成比、不同因素全胚冷冻率构成比、基础卵泡刺激素(FSH)水平、基础黄体生成素(LH)水平、基础雌二醇水平、基础睾酮水平、基础窦卵泡数(AFC)、获卵数、减数第2次分裂中期(MⅡ)卵母细胞数、正常受精率、同一取卵周期可移植胚胎数等比较，差异均无统计学意义(P>0.05)。②各组患者胚胎移植日子宫内膜厚度、移植胚胎数、优质胚胎率及内膜准备方案中人工周期率比较，差异均无统计学意义(P>0.05)。③ 4组患者累计临床妊娠率分别为64.5%、60.0%、58.7%、60.0%，组间比较，差异无统计学意义(χ²＝1.67, P＝0.64)。4组患者临床妊娠率依次为64.5%、36.5%、25.1%、18.8%，组间比较，差异有统计学意义(χ²＝143.02，P<0.01)。

同一促排卵周期增加FET次数，全胚冷冻患者累计临床妊娠率无显著变化。同时首次进行FET未妊娠者，随着FET次数增加，临床妊娠率显著降低。

To explore the clinical outcomes of different times of frozen embryo transfer (FET) cycles in the freeze-all cycles.

A total of 807 patients who underwent all embryos cryopreservation between January 2012 and September 2016 were analyzed. According to the different times of FET cycles in the same oocyte retrieval, they were divided into 4 groups: patients underwent FET once as group A (n=543), twice FET as group B (n=181), three times FET as group C (n=63), and four times FET as group D (n=20). The clinical medical records of two groups were retrospectively analyzed. The general clinical data, transfer cycles and the rates of cumulative pregnancy and clinical pregnancy among 4 groups were analyzed.

①There was no statistically difference with four groups in general characteristics which includes age, duration of infertility, infertility type, body mass index (BMI), basic follicle stimulating hormone (FSH) levels, basic luteinizing hormone(LH)levels, basic estradiol levels, basic testosterone levels, optimum number of oocytes, number of metaphase Ⅱ(MⅡ) oocytes, normal fertilization rate, number of available embryos(P>0.05). ②There was no statistically difference with four groups′clinical data including endometrial thickness, embryo number transferred, prime embryo rate and artificial cycle rate for endometrial preparation program (P>0.05). ③The cumulative pregnancy rates per collection cycle of 4 groups were 64.5%, 60.0%, 58.7% and 60.0%, respectively. And there was no significant difference (χ²=1.67, P=0.64). The clinical pregnancy rates were 64.5%, 36.5%, 25.1% and 18.8%, respectively. And there was significant difference(χ²=143.02, P<0.01).

The increasing of the number of FET transplantation in the same oocyte retrieval were not increased the total pregnancy rate of freeze-all cycles, but decreased the clinical pregnancy rate.