Proposed guidelines on the nomenclature and annotation of dynamic human embryo monitoring by a time-lapse user group

Abstract

There was no specific funding for the preparation of these proposed guidelines. Meetings were held opportunistically during scientific conferences and using online communication tools. H.N.C. is a scientific consultant for ESCO, supplier of Miri TL. I.E.A. is a minor shareholder in Unisense Fertilitech, supplier of the EmbryoScope. Full disclosures of all participants are presented herein. The remaining authors have no conflict of interest.

Does sperm origin affect embryo morphokinetic parameters?

“…Vitrolife® sequential media (Gothenburg, Sweden) were used for embryo culture, with embryos being cultured in G1plus® medium from day 0 to day 3 and then transferred to a new pre-equilibrated slide containing G2plus® medium and cultured from day 3 onwards. Each embryo was observed by detailed time-lapse analysis measuring the exact timing of the early developmental events in hours after ICSI procedure as described by Ciray and colleagues [13]. The terms t2, t3, t4, t5, t6, t7, and t8 were respectively used for exact timings of appearance of embryos with 2, 3, 4, 5, 6, 7, and 8 well-defined blastomeres.…”

“…The term CC2 was used to illustrate the duration of the two-cell stage, i.e., transition from a two-cell embryo to a three-cell embryo (t3-t2). In order to minimize the operatordependent variation, especially in blastocyst annotation, two embryologists were specifically trained and performed the annotation together according to the published guidelines [13].…”

Blastocyst collapse is not an independent predictor of reduced live birth: a time-lapse study

“…The duration of the TLM observation from the time point when the blastocyst reached full expansion and started pushing on the ZP (tfullB) until it reached a sufficiently expanded size for elective vitrification, and was removed from the TLM incubator, was calculated for each blastocyst. Early (PNf, t2-t9) and late (start of blastulation and full blastocyst) morphokinetic time points were scored in accordance with recently published consensus criteria (25). To determine the degree of blastocyst expansion more objectively, two additional TLM variables (texpB 1 , texpB 2 ) were also introduced (the time point when the horizontal diameter of the expanded blastocyst reached 130 and 160 mm) (26).…”

Morphokinetic parameters of early embryo development via time lapse monitoring and their effect on embryo selection and ICSI outcomes: a prospective cohort study

“…Evaluation of embryos was made based on the position of their time-points within the "normal" range, as proposed previously [39]. The events employed as morphological markers for embryo assessment and selection were:: t2: time to 2 cells (24-28 h), ii) cc2a: time between division from 2 to 3 cells (8-12 h), iii) t3: time to 3 cells (30-38 h), iv) s2: time between division from 3 to 4 cells (<45 min), v) t4: time to 4 cells (35-41 h), vi) cc3a: time between division from 4 to 5 cells (13-16 h), vii) t5: time to 5 cells (48-57 h), viii) s3: time between division from 5 to 8 cells (<6 h), ix) t8: time to 8 cells (50-59 h), as described elsewhere [39,40]. The embryos that showed the most optimal morphokinetic parameters were chosen for transfer.…”