OBJECTIVES: To evaluate the association between morphology grading and morphokinetic parameters in blastocyst stage embryos cultured in a time-lapse system. METHODS: This retrospective cohort study included patients offered fertility treatment with autologous oocytes in our clinic between October 2017 and May 2019 using a time-lapse system. The embryos were morphologically graded according to the criteria developed by Gardner and Schoolcraft and their morphokinetic parameters were recorded. RESULTS: Our results indicated that the time of pronuclei fading (tPNf), time to cleavage into two (t2), four (t4), and eight (t8) cells, and time to start of blastulation (tB) were significantly different according to the morphological quality of the blastocysts formed. In the early development stage, tPNf, t2 and t4 differed between good (AA, AB, BA, BB) and poor (CC) quality potential blastocysts. The 8-cell stage time separated embryos graded as AA blastocysts in terms of morphology from embryos graded as BB. Earlier tB correlated with higher quality embryos (AA, AB, BA). CONCLUSION: Our results showed that the first kinetic parameters (tPNf, t2, and t4) distinguished top-graded from low-graded blastocysts. Between top-graded blastocysts, t8 separated BB blastocysts from AA blastocysts. And finally, tB also told apart BB blastocysts from AA, AB, and BA blastocysts. These time-related parameters may be applied even in centers without time-lapse systems.
OBJECTIVES: To evaluate the association between morphology grading and morphokinetic parameters in blastocyst stage embryos cultured in a time-lapse system. METHODS: This retrospective cohort study included patients offered fertility treatment with autologous oocytes in our clinic between October 2017 and May 2019 using a time-lapse system. The embryos were morphologically graded according to the criteria developed by Gardner and Schoolcraft and their morphokinetic parameters were recorded. RESULTS: Our results indicated that the time of pronuclei fading (tPNf), time to cleavage into two (t2), four (t4), and eight (t8) cells, and time to start of blastulation (tB) were significantly different according to the morphological quality of the blastocysts formed. In the early development stage, tPNf, t2 and t4 differed between good (AA, AB, BA, BB) and poor (CC) quality potential blastocysts. The 8-cell stage time separated embryos graded as AA blastocysts in terms of morphology from embryos graded as BB. Earlier tB correlated with higher quality embryos (AA, AB, BA). CONCLUSION: Our results showed that the first kinetic parameters (tPNf, t2, and t4) distinguished top-graded from low-graded blastocysts. Between top-graded blastocysts, t8 separated BB blastocysts from AA blastocysts. And finally, tB also told apart BB blastocysts from AA, AB, and BA blastocysts. These time-related parameters may be applied even in centers without time-lapse systems.
Entities:
Keywords:
blastocyst; morphokinetics; morphology; time-lapse system
Authors: Kirstine Kirkegaard; Johnny Juhl Hindkjaer; Marie Louise Grøndahl; Ulrik Schiøler Kesmodel; Hans Jakob Ingerslev Journal: J Assist Reprod Genet Date: 2012-03-30 Impact factor: 3.412
Authors: Mariabeatrice Dal Canto; Giovanni Coticchio; Mario Mignini Renzini; Elena De Ponti; Paola Vittoria Novara; Fausta Brambillasca; Ruggero Comi; Rubens Fadini Journal: Reprod Biomed Online Date: 2012-08-02 Impact factor: 3.828
Authors: Liubin Yang; Mary Peavey; Khalied Kaskar; Neil Chappell; Lynn Zhu; Darius Devlin; Cecilia Valdes; Amy Schutt; Terri Woodard; Paul Zarutskie; Richard Cochran; William E Gibbons Journal: F S Rep Date: 2022-04-15