Duration of blastulation may be associated with ongoing pregnancy rate in single euploid blastocyst transfer cycles

Abstract

Not all euploid embryos implant, necessitating additional tools to select viable blastocysts in preimplantation genetic screening cycles. In this retrospective cohort study, 129 consecutive patients who underwent 129 single euploid blastocyst transfers in cryopreserved embryo transfer cycles were included. All embryos were individually cultured in a time-lapse incubator from intracytoplasmic sperm injection up to trophoectoderm biopsy. Twenty-three time-lapse morphokinetic variables were tested among patients with (n = 68) or without (n = 61) ongoing pregnancy. All 23 time-lapse morphokinetic variables, apart from duration of blastulation (tB-tSB), were comparable between patients with or without ongoing pregnancy. Duration of blastulation was significantly shorter in patients with ongoing pregnancy (8.1 ± 3.2 versus 9.5 ± 3.4 h; P = 0.014); shorter duration of blastulation remained an independent predictor for ongoing pregnancy, when tested by logistic regression analysis (OR 0.81; 95% CI 0.70 to 0.93). One important limitation of this study, and a reason for caution, is the use of multiple comparisons, which can lead to differences at the 0.05 level simply by chance or random variation. Nonetheless, the study suggests that when more than one euploid blastocyst is available, priority might be given to those with a shorter duration of blastulation.

Does Embryonic Culture Environment Affect Ploidy Rates in ART Cycles: A Single Center Study in UK

“…As such, this study indeed demonstrated that euploidy rate in oocyte donors is treatment center related. Studies have shown that suboptimal culture systems can affect gene expression and imprinting (Ho et al 1994Ho et al 1995; Doherty et al 2000; Fernandez-Gonzalez et al 2010; Market Velker et al 2010) demonstrating that embryonic chromosomal abnormality could be partly iatrogenic ( 5 , 7 ).…”

“…However, experimental evidence and clinical data suggest that a number of treatment related factors may affect the incidence of chromosomal imbalance in embryos with exclusion of age ( 3 , 5 – 7 ). Factors such as culture conditions, gamete manipulation, high oxygen tension during culture, immaturity, and post maturity of oocytes at the point of fertilization ( 3 , 5 , 7 , 8 ) can possibly induce gene expression and chromosomal abnormalities.…”

“…However, experimental evidence and clinical data suggest that a number of treatment related factors may affect the incidence of chromosomal imbalance in embryos with exclusion of age ( 3 , 5 – 7 ). Factors such as culture conditions, gamete manipulation, high oxygen tension during culture, immaturity, and post maturity of oocytes at the point of fertilization ( 3 , 5 , 7 , 8 ) can possibly induce gene expression and chromosomal abnormalities. Some studies have also shown that ovulation induction protocol used for standard IVF may increase the frequency of meiotic errors in eggs, thus secondarily increasing aneuploidy in the resulting embryos ( 3 , 9 , 10 ).…”

“…Therefore, laboratory culture conditions affect the incidence of chromosomal imbalances in embryos across different centers ( 5 ). Some studies have shown a significant increase in clinical pregnancy rate (CPR) and live birth rate (LBR) from embryos cultured in time lapse monitoring (TLM) incubators compared to a standard incubator ( 7 , 11 , 12 ).…”

Validation of ART Calculator for Predicting the Number of Metaphase II Oocytes Required for Obtaining at Least One Euploid Blastocyst for Transfer in Couples Undergoing in vitro Fertilization/Intracytoplasmic Sperm Injection

“…In the former, biopsied trophectoderm samples were transferred to 1xPBS solution in PCR tubes, stored at −20 • C until 24 samples were collected, and then shipped to the central laboratory. Whole-genome amplification was performed using the Sureplex amplification kit (Illumina, San Diego, CA, USA) (35). After WGA, amplification was checked in gel electrophoresis, and DNA concentration was measured using the dsDNA high-sensitivity assay kit (Qubit R ; Life Technologies, Waltham, MA, USA).…”