Hadar Amir1, Shiri Barbash-Hazan1, Yael Kalma1, Tsvia Frumkin1, Mira Malcov1, Nivin Samara1, Joseph Hasson1, Adi Reches1, Foad Azem1, Dalit Ben-Yosef2,3. 1. IVF Lab & Wolfe PGD-Stem Cell Lab, Racine IVF Unit, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel, affiliated to the Sackler Faculty of Medicine, Tel Aviv University, 6 Weizman Street, 6423906, Tel Aviv, Israel. 2. IVF Lab & Wolfe PGD-Stem Cell Lab, Racine IVF Unit, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Tel Aviv, Israel, affiliated to the Sackler Faculty of Medicine, Tel Aviv University, 6 Weizman Street, 6423906, Tel Aviv, Israel. dalitb@tlvmc.gov.il. 3. Department of Cell Biology and Development, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel. dalitb@tlvmc.gov.il.
Abstract
PURPOSE: The purpose of the study was to compare the morphokinetic parameters of embryos carrying balanced chromosomal translocations with those carrying unbalanced chromosomal translocations using time-lapse microscopy. METHODS: The study group included 270 embryos that underwent biopsies on day 3 for preimplantation genetic diagnosis (PGD) for chromosomal translocations in our unit between 2013 and 2015. All embryos were incubated under time-lapse microscopy and evaluated for timing of developmental events up to day 5. The timing of these events was compared between balanced and unbalanced embryos, potentially viable and nonviable variants, and maternal versus paternal inheritance of the translocation. RESULTS: The PGD analysis found that 209 (77%) of the 270 biopsied embryos carried an unbalanced translocation. Embryos carrying unbalanced translocations, which are expected to lead to implantation failure or miscarriage, cleaved less synchronously and were delayed in time of cleavage to the 4-cell stage (t4) and in time of start of blastulation (tSB) compared with balanced embryos (P < 0.05). Furthermore, embryos carrying nonviable translocations demonstrated a significant delay at the time of pronuclei fading (tPNf) compared with those carrying potentially viable translocations (P < 0.05). Embryos whose unbalanced translocations were of maternal origin were significantly delayed in most of the morphokinetic parameters (including tPNf, t2, t3, t4, t6, t7, t8, cc2, s2, and tSB) compared with embryos carrying balanced translocations (P < 0.05). CONCLUSIONS: Embryos carrying unbalanced chromosomal translocations mainly of maternal origin undergo delayed development and asynchronous cleavage that may lead to implantation failure or miscarriage.
PURPOSE: The purpose of the study was to compare the morphokinetic parameters of embryos carrying balanced chromosomal translocations with those carrying unbalanced chromosomal translocations using time-lapse microscopy. METHODS: The study group included 270 embryos that underwent biopsies on day 3 for preimplantation genetic diagnosis (PGD) for chromosomal translocations in our unit between 2013 and 2015. All embryos were incubated under time-lapse microscopy and evaluated for timing of developmental events up to day 5. The timing of these events was compared between balanced and unbalanced embryos, potentially viable and nonviable variants, and maternal versus paternal inheritance of the translocation. RESULTS: The PGD analysis found that 209 (77%) of the 270 biopsied embryos carried an unbalanced translocation. Embryos carrying unbalanced translocations, which are expected to lead to implantation failure or miscarriage, cleaved less synchronously and were delayed in time of cleavage to the 4-cell stage (t4) and in time of start of blastulation (tSB) compared with balanced embryos (P < 0.05). Furthermore, embryos carrying nonviable translocations demonstrated a significant delay at the time of pronuclei fading (tPNf) compared with those carrying potentially viable translocations (P < 0.05). Embryos whose unbalanced translocations were of maternal origin were significantly delayed in most of the morphokinetic parameters (including tPNf, t2, t3, t4, t6, t7, t8, cc2, s2, and tSB) compared with embryos carrying balanced translocations (P < 0.05). CONCLUSIONS: Embryos carrying unbalanced chromosomal translocations mainly of maternal origin undergo delayed development and asynchronous cleavage that may lead to implantation failure or miscarriage.
Authors: E Mateu-Brull; L Rodrigo; V Peinado; A Mercader; I Campos-Galindo; F Bronet; S García-Herrero; M Florensa; M Milán; C Rubio Journal: J Assist Reprod Genet Date: 2019-11-06 Impact factor: 3.412
Authors: Robert West; Arri Coomarasamy; Lorraine Frew; Rachel Hutton; Jackson Kirkman-Brown; Martin Lawlor; Sheena Lewis; Riitta Partanen; Alex Payne-Dwyer; Claudia Román-Montañana; Forough Torabi; Sofia Tsagdi; David Miller Journal: Hum Reprod Date: 2022-05-30 Impact factor: 6.353