Objectives: As a remedy for the failure of in vitro fertilization (IVF), rescue intracytoplasmic sperm injection (R-ICSI) has been widely carried out, but it has failed to significantly improve the fertilization rate and clinical pregnancy rate. Sperm DNA fragmentation index (DFI) was highly correlated with pregnancy outcome of artificial assisted reproduction. This study aims to investigate the effect of the sperm DFI on the outcome of R-ICSI and the clinical value of R-ICSI.
Methods: This retrospective analysis was conducted among 140 infertile couples receiving R-ICSI in from January 2014 to December 2019. The subjects were assigned into a total fertilization failure (TFF)+low DFI group (R-ICSI after TFF and DFI<30%) (n=63), a TFF+high DFI group (R-ICSI after TFF and DFI≥30%) (n=16), a partial fertilization failure (PFF)+low DFI group (R-ICSI after PFF and DFI<30%) (n=52), a PFF+high DFI group (R-ICSI after PFF and DFI≥30%) (n=9). All transferred embryos were come from R-ICSI. The general clinical data [infertility duration, male age, female age, basal serum level of follicle stimulating hormone (FSH), basal serum level of luteinizing hormone (LH), antral follicle count, endometrial thickness of human chorionic gonadotropin (HCG) day, and eggs] and R-ICSI cycle outcomes (fertilization rate, normal fertilization rate, cleavage rate, good embryo rate, implantation rate, clinical pregnancy rate and live birth rate) were analyzed. In addition, the effect of R-ICSI on the fertilization outcome of conventional IVF total fertilization failure and partial fertilization failure was explored.
Results: There was no significant difference in the general clinical data and R-ICSI cycle outcome between the TFF+low DFI group and the TFF+high DFI group (all P>0.05). There was no significant difference in the general clinical data between the PFF+low DFI group and the PFF+high DFI group (all P>0.05). The fertilization rate and normal fertilization rate in the PFF+low DFI group were significantly higher than those in the PFF+high DFI group (85.40% vs 72.41%, 71.90% vs 58.62%, respectively; both P<0.05). However, there was no significant difference in cleavage rate, good embryo rate, implantation rate, clinical pregnancy rate, and live birth rate between the 2 groups (all P>0.05). The R-ICSI cycle of TFF: A total of 79 fresh cycles, 57 fresh transplant cycles, a total of 761 unfertilized oocytes, and 584 M II oocytes were treated with R-ICSI, the fertilization rate was 83.22%, the normal fertilization rate was 75.51%, the cleavage rate was 98.15%, the good embryo rate was 40.74%, the implantation rate was 30.56%, and the clinical pregnancy rate was 43.86%; 29 live births were obtained. The R-ICSI cycle of PFF: A total of 61 fresh cycles, 31 fresh transplant cycles, a total of 721 unfertilized oocytes, and 546 M II oocytes were treated with R-ICSI; the fertilization rate was 83.33%, the normal fertilization rate was 69.78%, the cleavage rate was 97.36%, the good embryo rate was 44.39%, the implantation rate was 25.42%, and the clinical pregnancy rate was 45.16%; 12 live births were obtained.
Conclusions: In the case of partial fertilization failure of IVF, the sperm DFI affects the fertilization rate and normal fertilization rate of R-ICSI; whether it is a TFF of IVF or PFF of IVF, ICSI can be used as an effective remedy way.
目的: 补救卵胞浆内单精子注射术(rescue intracytoplasmic sperm injection，R-ICSI)作为体外受精(in vitro fertilization，IVF)失败的补救方案，目前已广泛开展，但是未能明显提高受精率、临床妊娠率等。精子DNA断裂指数(DNA fragmentation index，DFI)与人工辅助生殖妊娠结局高度相关。本研究旨在探讨精子DFI对R-ICSI结局的影响及R-ICSI的临床价值。方法: 回顾性分析2014年1月至2019年12月间在广西壮族自治区人民医院生殖医学与遗传中心IVF受精失败后行R-ICSI的140对不孕不育症夫妇，并将其分为完全受精失败(total fertilization failure，TFF)后行R-ICSI且DFI<30%(TFF+低DFI)组(n=63)、TFF后行R-ICSI且DFI≥30%(TFF+高DFI)组(n=16)、部分受精失败(partial fertilization failure，PFF)后行R-ICSI且DFI<30%(PFF+低DFI)组(n=52)、PFF后行R-ICSI且DFI≥30%(PFF+高DFI)组 (n=9)。新鲜移植周期的胚胎来源均为R-ICSI。观察比较不同精子DFI在两种受精失败情况下患者的一般情况(不育年限、男方年龄、女方年龄、基础促卵泡素(follicle stimulating hormone，FSH)水平、基础黄体生成素(luteinizing hormone，LH)水平、窦卵泡个数、人绒毛膜促性腺激素(human chorionic gonadotropin，HCG)日子宫内膜厚度、获卵数)和R-ICSI周期结局(受精率、正常受精率、卵裂率、优质胚胎率、种植率、临床妊娠率及活产率)。结果: TFF+低DFI组和TFF+高DFI组患者的一般情况和R-ICSI周期结局差异均无统计学意义(均P>0.05)。PFF+低DFI组和PFF+高DFI组患者的一般情况差异均无统计学意义(均P>0.05)。PFF+低DFI组受精率、正常受精率均高于PFF+高DFI组，差异均有统计学意义(分别为85.40% vs 72.41%，71.90% vs 58.62%；均P<0.05)；但2组患者卵裂率、优质胚胎率、种植率、临床妊娠率及活产率差异均无统计学意义(均P>0.05)。TFF的R-ICSI周期共79个新鲜周期，57个新鲜移植周期，761个未受精卵，对584个M II期卵子行R-ICSI，受精率为83.22%，正常受精率为75.51%，卵裂率为98.15%，优质胚胎率为40.74%，种植率为30.56%，临床妊娠率为43.86%，获得29个活产儿。PFF的R-ICSI周期共61个新鲜周期，31个新鲜移植周期，721个未受精卵，对546个M II期卵子行R-ICSI，受精率为83.33%，正常受精率为69.78%，卵裂率为97.36%，优质胚胎率为44.39%，种植率为25.42%，临床妊娠率为45.16%，获得12个活产儿。结论: 在常规IVF PFF的情况下，精子DFI影响R-ICSI受精率和正常受精率；对于常规IVF TFF或PFF，ICSI都可作为有效补救方案。.
Keywords: outcome; partial fertilization failure; rescue intracytoplasmic sperm injection; sperm DNA fragmentation index; total fertilization failure.