Department of Reproductive Medicine Center, The Affiliated Changzhou Maternal and Child Health Care Hospital of Nanjing Medical University, Changzhou, China.
Front Endocrinol (Lausanne). 2021 Dec 24;12:785658. doi: 10.3389/fendo.2021.785658. eCollection 2021.
To determine whether the embryo developmental stage affects biochemical or clinical pregnancy loss in young women undergoing frozen-thawed embryo transfer (FET) and to investigate the underlying mechanism.
This was a retrospective study including a total of 18,34 β-HCG (human chorionic gonadotropin)-positive FET cycles. According to the morphological appearance (MA) of transferred blastocysts, FET cycles with blastocysts were divided into two groups: Group A: morphologically good (MG) blastocysts only, and Group B: at least one morphologically non-good (MNG) blastocyst. FET cycles with day 3 cleavage embryos were assigned as Group C. Biochemical and clinical pregnancy loss were the main outcome measures.
We predicted 78% -formed MG and 53.9% -formed day 5 blastocysts in Group C. (a) Including cases in Group A and Group B for binary logistic regression, we showed that Group B and day 6 blastocysts had significantly higher rates of BPL and CPL than Group A and day 5 blastocysts, respectively. (b) Including cases in Group A, Group B, and Group C for binary logistic regression, we showed that Group C had a significantly higher rate of BPL than Group A and day 5 blastocysts and a similar rate of BPL as Group B and day 6 blastocysts. Group C had a higher rate of CPL than Group A (p=0.071) and day 5 blastocysts (p=0.039), and a lower rate of CPL than Group B (p=0.199) and day 6 blastocysts (p=0.234).
(1) MA and days of usable blastocysts could serve as independent factors affecting the occurrence of BPL and CPL. (2) Transfer of day 3 cleavage embryos may produce "unusable blastocysts" , which significantly increased the rate of BPL. (3) The rate of CPL resulting from the transfer of day 3 embryos may depend on the rate of -formed MG or day 5 blastocysts. Our study indicated that the difference in the BPL or CPL between transfer of blastocysts and day 3 cleavage embryos may largely depend on the quality of embryos transferred.
为了确定胚胎发育阶段是否会影响接受冻融胚胎移植（FET）的年轻女性的生化或临床妊娠丢失，并探讨其潜在机制。
这是一项回顾性研究，共纳入 1834 个β-HCG（人绒毛膜促性腺激素）阳性 FET 周期。根据转移囊胚的形态外观（MA），将有囊胚的 FET 周期分为两组：A 组：形态良好（MG）囊胚，B 组：至少有一个形态不良（MNG）囊胚。将第 3 天卵裂胚胎的 FET 周期分为 C 组。生化和临床妊娠丢失是主要观察结局。
我们预测 C 组中 78%可形成 MG 和 53.9%可形成第 5 天的囊胚。（a）将 A 组和 B 组的病例纳入二元逻辑回归，结果显示 B 组和第 6 天的囊胚的生化妊娠丢失（BPL）和临床妊娠丢失（CPL）发生率均显著高于 A 组和第 5 天的囊胚。（b）将 A 组、B 组和 C 组的病例纳入二元逻辑回归，结果显示 C 组的 BPL 发生率显著高于 A 组和第 5 天的囊胚，与 B 组和第 6 天的囊胚相似。C 组的 CPL 发生率高于 A 组（p=0.071）和第 5 天的囊胚（p=0.039），低于 B 组（p=0.199）和第 6 天的囊胚（p=0.234）。
（1）MA 和可用囊胚的天数可作为影响生化和临床妊娠丢失的独立因素。（2）第 3 天卵裂胚胎的移植可能产生“不可用囊胚”，显著增加 BPL 的发生率。（3）第 3 天胚胎移植的 CPL 发生率可能取决于 MG 或第 5 天囊胚的形成率。本研究表明，囊胚移植与第 3 天卵裂胚胎之间的 BPL 或 CPL 差异在很大程度上取决于移植胚胎的质量。
