HUWE1 is a HECT domain containing ubiquitin ligase implicated in neurogenesis, spermatogenesis and cancer development. The purpose of the current study is to investigate the role of HUWE1 in early embryo development. Here we demonstrate that Huwe1 is expressed in both nucleus and cytoplasm of preimplantation mouse embryos as well as gametes. Hypoxia (5% O2) treatment could significantly increas...

Abstract Study question Is artificial removal of the zona pellucida (ZP) at pronuclear stage effective in patients with poor quality embryos severe fragmentation? Summary answer Artificial ZP significantly improved culture results fragmentation. What is known already In 2020, Yumoto et al. first reported that (ZP-free) decreased rate fragmentation and outcomes 3 pronuclei (3PN) reaching to good...

STUDY QUESTION What are the aneuploidy rates and incidence of mosaicism in good-quality human preimplantation embryos. SUMMARY ANSWER High-level mosaicism and structural aberrations are not restricted to arrested or poorly developing embryos but are also common in good-quality IVF embryos. WHAT IS KNOWN ALREADY Humans, compared with other mammals, have a poor fertility rate, and even IVF tr...

STUDY QUESTION Does conventional blastocyst morphological evaluation correlate with euploidy (as assessed by comprehensive chromosome screening (CCS) of trophectoderm (TE) biopsies) and implantation potential? SUMMARY ANSWER A moderate relation between blastocyst morphology and CCS data was observed but the ability to implant seems to be mainly determined by the chromosomal complement of prei...

background: multiple factors have been suggested for prediction of pregnancy in intracytoplasmic sperm injection (icsi) cycles such as the number of injected oocytes, fertilization rate, embryo morphology and quality of transferred embryos. predictive value of these factors is important in icsi outcome. objectives: to evaluate the role of embryo morphology for prediction of pregnancy in icsi cy...

DNA methylation is a key epigenetic modification which is essential for normal embryonic development. Major epigenetic reprogramming takes place during gametogenesis and in the early embryo; the complex DNA methylation patterns are established and maintained by DNA methyltransferases (DNMTs). However, the influence of assisted reproductive technologies (ART) on DNA methylation reprogramming enz...

BACKGROUND The large number (30) of permanent human embryonic stem cell (hESC) lines and additional 29 which did not continue growing, in our laboratory at Karolinska Institutet have given us a possibility to analyse the relationship between embryo morphology and the success of derivation of hESC lines. The derivation method has been improved during the period 2002-2009, towards fewer xeno-comp...