Sifer C, Sellami A, Poncelet C, Kulski P, Martin-Pont B, Bottero J, Porcher R, Cedrin-Durnerin I, Hugues J N, Wolf J P
Service d'Histologie-Embryologie-Cytogénétique, Laboratoire de Biologie de la Reproduction, Hôpital Jean Verdier, Bondy cedex, France.
Hum Reprod. 2006 Sep;21(9):2384-9. doi: 10.1093/humrep/del149. Epub 2006 Jun 13.
Assisted hatching (AH) in fresh embryo transfer (ET) could be associated with increased implantation rates. However, very few prospective randomized studies have specifically addressed the issue of AH during frozen-thawed embryo transfers (FET) cycles, those that have reported controversial results. The aim of this study was to evaluate the benefit of an enzymatic zona pellucida treatment of frozen-thawed embryos before transfer.
This was a prospective study including 125 non-donor FET cycles from 125 infertile couples. FETs were randomly allocated into AH group (n = 61, embryos pretreated with pronase 5 IU/ml for 1 min at 37 degrees C) or control group (n = 64, untreated embryos). Zona pellucida thickness was measured for each transferred embryo. The main outcome parameters were clinical pregnancy and implantation rates.
The two groups were comparable regarding mean women's age, duration and indications of infertility, IVF outcome after fresh ETs, numbers and quality of fresh and frozen embryos, frozen-thawed embryo survival rates and blastomeres survival indexes. Despite a statistically significant decrease of zona pellucida thickness after pronase treatment [(mean +/- SD) 18.5 +/- 2.25 versus 14.5 +/- 2.75 microm; P < 0.0001], implantation (9.6 versus 9.2%) and clinical pregnancy rates (18.0 versus 17.2%) were not statistically different after FETs, with a similar mean number of embryos transferred between AH and control groups, respectively.
Within the constraints of our protocol, partial enzymatic digestion of zona pellucida by pronase was not related with any benefit of the FET outcome especially concerning the implantation ability of frozen-thawed embryos.
新鲜胚胎移植（ET）中的辅助孵化（AH）可能与着床率增加有关。然而，很少有前瞻性随机研究专门探讨冻融胚胎移植（FET）周期中的AH问题，已报道的研究结果存在争议。本研究的目的是评估移植前对冻融胚胎进行酶解透明带处理的益处。
这是一项前瞻性研究，纳入了125对不孕夫妇的125个非供体FET周期。FET被随机分为AH组（n = 61，胚胎在37℃下用5 IU/ml链霉蛋白酶预处理1分钟）或对照组（n = 64，未处理的胚胎）。测量每个移植胚胎的透明带厚度。主要结局参数为临床妊娠率和着床率。
两组在女性平均年龄、不孕持续时间和指征、新鲜ET后的体外受精结局、新鲜和冷冻胚胎的数量和质量、冻融胚胎存活率和卵裂球存活指数方面具有可比性。尽管链霉蛋白酶处理后透明带厚度有统计学显著降低[（均值±标准差）18.5±2.25对14.5±2.75微米；P < 0.0001]，但FET后着床率（9.6%对9.2%）和临床妊娠率（18.0%对17.2%）无统计学差异，AH组和对照组移植的平均胚胎数相似。
在我们的方案限制范围内，链霉蛋白酶对透明带的部分酶解与FET结局的任何益处无关，尤其是在冻融胚胎的着床能力方面。
