Department of IVF, ARC International Fertility and Research Centre, Chennai, Tamil Nadu, India.
Department of Reproductive Medicine, ARC International Fertility and Research Centre, Chennai, Tamil Nadu, India.
PeerJ. 2022 Aug 26;10:e13935. doi: 10.7717/peerj.13935. eCollection 2022.
Transfer of embryos at the blastocyst stage is one of the best approaches for achieving a higher success rate in fertilization (IVF) treatment as it demonstrates an improved uterine and embryonic synchrony at implantation. Despite novel biochemical and genetic markers proposed for the prediction of embryo viability in recent years, the conventional morphological grading of blastocysts remains the classical way of selection in routine practice. This study aims to investigate the association between the morphological features of blastocysts and pregnancy outcomes.
This prospective study included women undergoing single or double frozen blastocyst transfers following their autologous cycles in a period between October 2020 and September 2021. The morphological grades (A-good, B-average, and C-poor) of inner cell mass (ICM) and trophectoderm (TE) of blastocysts with known implantation were compared to assess their predictive potential of pregnancy outcome. It was further explored by measuring the relationship between the two variables using logistic regression and receiver operating characteristic (ROC) analysis.
A total of 1,972 women underwent frozen embryo transfer (FET) cycles with a total of 3,786 blastocysts. Known implantation data (KID) from 2,060 blastocysts of 1,153 patients were subjected to statistical analysis, the rest were excluded. Implantation rates (IR) from transfer of ICM/TE grades AA, AB, BA, BB were observed as 48.5%, 39.4%, 23.4% and 25% respectively. There was a significantly higher IR observed in blastocysts with ICM grade A ( < 0.001) than those with B irrespective of their TE scores. The analysis of the interaction between the two characteristics confirmed the superiority of ICM over TE as a predictor of the outcome. The rank biserial correlation value for ICM was also greater compared to that of TE (0.11 vs 0.05).
This study confirms that the morphology of ICM of the blastocyst is a stronger predictor of implantation and clinical pregnancy than that of TE and can be utilized as a biomarker of viability.
囊胚期胚胎移植是提高受精（IVF）治疗成功率的最佳方法之一，因为它在着床时显示出改善的子宫和胚胎同步性。尽管近年来提出了新的生化和遗传标记物来预测胚胎活力，但常规形态学评分仍然是常规实践中的经典选择方法。本研究旨在探讨囊胚形态特征与妊娠结局之间的关系。
这项前瞻性研究包括 2020 年 10 月至 2021 年 9 月期间接受自体周期单或双冷冻囊胚移植的女性。比较具有已知着床的囊胚的内细胞团（ICM）和滋养外胚层（TE）的形态学等级（A-好、B-平均和 C-差），以评估其对妊娠结局的预测潜力。进一步通过使用逻辑回归和接收器操作特征（ROC）分析来测量这两个变量之间的关系来探索。
共有 1972 名女性接受了冷冻胚胎移植（FET）周期，共有 3786 个囊胚。对 1153 名患者的 2060 个囊胚的已知着床数据（KID）进行了统计分析，其余的被排除在外。ICM/TE 等级 AA、AB、BA、BB 的移植胚胎着床率（IR）分别为 48.5%、39.4%、23.4%和 25%。ICM 等级为 A 的囊胚的 IR 明显更高（<0.001），而不管其 TE 评分如何。对两个特征之间的相互作用的分析证实了 ICM 作为结局预测指标的优越性。与 TE 相比，ICM 的秩双列相关值也更大（0.11 对 0.05）。
本研究证实，囊胚 ICM 的形态比 TE 更能预测着床和临床妊娠，可作为活力的生物标志物。
