标题：Clinical outcomes following frozen-thawed blastocyst transfers with blastocysts derived from different cell numbers on day 3: a retrospective cohort study
作者：Zhao H.; Liu H.; Li M.; Wu K.
作者机构：[Zhao, H] Center for Reproductive Medicine, Shandong Provincial Hospital Affiliated to Shandong University, National Research Center for Assisted Repr 更多
通讯作者地址：[Wu, K] Center for Reproductive Medicine, Shandong Provincial Hospital Affiliated to Shandong University, National Research Center for Assisted Reprod 更多
来源：Journal of Assisted Reproduction and Genetics
关键词：Cell number; Clinical pregnancy rate; Frozen blastocyst transfer; Live birth rate; Neonatal outcomes
摘要：Purpose: To evaluate clinical outcomes after frozen-thawed blastocyst transfer (TBT) with blastocysts which were derived from different cell numbers on day 3. Methods: The study included 1444 patients undergoing single autologous frozen-thawed blastocyst transfer cycles, which were allocated to five groups according to the cell numbers on day 3 of the transferred blastocysts: ≤ 6-cell (n = 109), 7-cell (n = 169), 8-cell (n = 811), 9-cell (n = 136), and ≥ 10-cell (n = 219). Results: The LBR of the ≤ 6-cell group was found to be statistically lower than that of the 8-cell group in single TBT cycles which had been transferred with fair quality blastocysts (defined as 4BB according to Gardner’s grading scale) (41.28% vs 55.73%, P = 0.004), while the miscarriage rate was significantly higher for the ≤ 6-cell group compared with the 8-cell group (25.00% vs 13.74%, P = 0.02). No differences were found between the two groups in terms of cPR (P = 0.06). However, for blastocysts categorized as high quality according to Gardner’s classification (defined as 4AA/4AB/4BA), cPR, LBR, and early miscarriage rates did not differ between the two groups (P = 0.76, P = 0.44, P = 0.40, respectively). Conclusions: When transferring blastocysts, an evaluation of the cleavage stage should be performed along with blastocyst morphology to shorten the time of conceiving. © 2020, Springer Science+Business Media, LLC, part of Springer Nature.