Kepler University, Department of Gynecology, Obstetrics, and Gynecological Endocrinology, Krankenhausstrasse 26-30, Linz Upper Austria, Austria.
University for Life, Beethovenstrasse 9, Graz Styria, Austria.
Reprod Biomed Online. 2020 Feb;40(2):191-199. doi: 10.1016/j.rbmo.2019.11.004. Epub 2019 Nov 28.
To study the origin and temporal behaviour of cytoplasmic strings spanning the blastocoel (main objective) and their influence on treatment outcome (secondary objective).
This retrospective analysis of prospectively collected data was set up in a university medical centre. Patients who either underwent fresh (n = 95) or vitrified-warmed (n = 55) single blastocyst transfer were included. Time-lapse sequences of in-vitro developed blastocysts were screened for the presence of cytoplasmic strings. Pregnancies in string-positive and string-negative transfers were followed up to live birth.
A total of 387 blastocysts were obtained in the fresh cycles of 100 patients, corresponding to a blastocyst formation rate of 62.4%. Cytoplasmic strings were first detected around full stage (108.5 ± 6.4 h) in 170 blastocysts (43.9%). The number of strings varied (range: 1-7) and the duration of visibility was 5.2 ± 3.5 h. The occurrence of cytoplasmic strings was significantly associated with the presence of blastocoelic collapses (P < 0.001) but not with any of the annotated morphokinetic parameters. Live birth and neonatal outcome were the same for both string-positive and string-negative pregnancies. Moreover, collapses did not affect treatment outcome.
Time-lapse analysis of cytoplasmic strings at the blastocyst stage revealed that this morphological feature was not a negative predictor as previously reported. Although physiologically normal, at least some of the cytoplasmic strings are an artefact, possibly associated with blastocoelic collapses.
研究贯穿囊胚腔的细胞质串（主要目标）的起源和时间行为及其对治疗结果的影响（次要目标）。
本研究为前瞻性收集数据的回顾性分析，在一所大学医学中心进行。纳入接受新鲜（n=95）或玻璃化冷冻-解冻（n=55）单个囊胚移植的患者。对体外发育的囊胚的时差序列进行细胞质串的存在筛查。对有细胞质串和无细胞质串的移植妊娠进行随访至活产。
在 100 名患者的新鲜周期中获得了总共 387 个囊胚，囊胚形成率为 62.4%。在 170 个囊胚（43.9%）中，首次在完全期（108.5±6.4 h）检测到细胞质串。串的数量不同（范围：1-7），可见持续时间为 5.2±3.5 h。细胞质串的发生与囊胚腔塌陷显著相关（P<0.001），但与任何注释的形态动力学参数均无关。有细胞质串和无细胞质串的妊娠的活产和新生儿结局相同。此外，塌陷并不影响治疗结果。
在囊胚阶段对细胞质串进行时差分析表明，与之前报道的相反，这种形态特征不是负面预测因素。尽管在生理上是正常的，但至少一些细胞质串是一种人为假象，可能与囊胚腔塌陷有关。
