M. Cetinkaya

Relative kinetic expressions defining cleavage synchronicity are better predictors of blastocyst formation and quality than absolute time points

PurposeMorphology alone is not enough for the selection of the embryo (s) with the highest implantation potential and time-lapse imaging has added embryo development kinetics as another selection criterion. Therefore, a combination of morphology with kinetics has inspired a new field termed “morphokinetics”, providing a new way of evaluating and selecting embryos. The aim of the study was to identify a criterion solely based on morphokinetic data and available up to the 8-cell stage (t8) to predict blastocyst formation and quality.MethodsThe study included 3,354 embryos, with annotations up to t8, and cultured until day 5 from 626 infertile patients. A total of 17 kinetic expressions, either absolute cleavage timings and time intervals or time ratios were tested retrospectively for the prediction of blastocyst formation and quality.ResultsRelative timings (t8-t5, the cleavage synchronicity from 4 to 8 cells and from 2 to 8 cells) were found to be better indicators of blastocyst formation and quality when compared to absolute time-points. Especially, the cleavage synchronicity from 2 to 8 cells (CS2-8) = ((t3-t2) + (t5-t4))/(t8-t2)) was found to be the best predictor available on day 3 for blastocyst formation and quality (AUC:0.786; sensitivity: 83.43; specificity: 62.46).ConclusionsTime intervals and relative ratios based on selected cleavage cycles defining synchronicity allowed a specific analysis providing high predictivity of blastocyst formation and quality.

Comparison of Blastocyst Development and Cycle Outcome in Patients with eSET Using Either Conventional or Time Lapse Incubators. A Prospective Study of Good Prognosis Patients

The aim of this study is to compare blastocyst development and cycle outcomes of good prognosis elective single embryo transfer patients using conventional or time lapse incubators. A randomized st...

Recent advances in preimplantation genetic diagnosis

Preimplantation genetic diagnosis (PGD) gives couples who are at risk of having a child with an inherited genetic disorder or chromosome abnormality, a chance to have an unaffected child without undergoing termination or miscarriage of an affected pregnancy. Embryos obtained from in-vitro fertilisation (IVF) with or without intracytoplasmic sperm injection are tested genetically prior to selective transfer of unaffected ones into the uterus. The physical and psychological complications of a termination or miscarriage, especially in repeated situations, should not be underestimated. In PGD, DNA can be obtained by blastomere biopsy at the cleavage stage, trophectoderm cell biopsy when an embryo has developed to the blastocyst stage or biopsy of one or both polar bodies. Compared with cleavage stage biopsy, trophectoderm biopsy does not adversely impact the embryo, although vitrification and cryopreservation of the embryo may be required to allow time for genetic analysis.1 Although polar body biopsy is less invasive, it is less predictive of actual clinical outcome than direct embryo assessment.2 Genetic laboratories have developed their own protocols to perform different molecular tests on the limited amount of DNA obtained from biopsy. Traditionally, fluorescent in-situ hybridisation is used for cytogenetic diagnosis, and polymerase chain reaction for molecular diagnosis. New technologies, including array comparative genomic hybridisation (CGH) and single nucleotide polymorphism (SNP) microarrays, can improve diagnostic accuracy.3,4 The single-cell whole genome amplification (WGA) method allows subsequent mutation study, directly by minisequencing and/or indirectly by linkage analysis alongside the mutation test. It also allows simultaneous PGD for more than one indication.5 The indications for PGD are increasing. Common ones include single-gene disorders, X-linked diseases, and inherited chromosome abnormalities. Preimplantation genetic diagnosis of predisposition to inherited cancer such as breast cancer (BRCA mutation) is also emerging.6 Nonetheless, social sexing is prohibited in Hong Kong and Europe. Legislation and regulation of PGD also vary among different countries. Aneuploidy is the most common cause of repeated implantation failure and recurrent Hong Kong Med J 2015;21:296–7 DOI: 10.12809/hkmj154638 KY Leung*, MD, FHKAM (Obstetrics and Gynaecology)

Therapeutic success of HSCT by preimplantation haplotyping, follow-up of 520 cycles

Introduction: Many inherited and acquired pediatric hematological disorders can be cured only by hematopoietic stem cell transplantation (HSCT). However, the success of HSCT depends on how well human leukocyte antigen (HLA) haplotypes of recipient and the donor match to each other. Unfortunately, an HLA identical related donor is only available for 15-30% of the cases and the probability of finding an HLA matched unrelated donor is extremely small. Preimplantation genetic diagnosis combined with HLA typing is an alternative technique, which offers the possibility of selecting unaffected embryos that are HLA-identical with the sick child with the aim of possible use of stem cells from the resulting baby in future. This alternative source of HSCT known as “preimplantation HLA matching” has been a well-established and realistic treatment option especially for pediatric hematological disorders since 2001.