Metabolic profile of in vitro derived human embryos is not affected by the mode of fertilization

Sturmey, Roger G; Leary, Christine

Abstract

The pattern of metabolism by early embryos in vitro has been linked to a range of phenotypes, including viability. However, the extent to which metabolic function of embryos is modified by specific methods used during ART has yet to be fully described. This study has sought to determine if the mode of fertilization used to create embryos affects subsequent embryo metabolism of substrates. A metabolic profile, including consumption of key substrates and the endogenous triglyceride content of individual IVF and ICSI supernumerary embryos, was assessed and compared. Embryo development and quality was also recorded. All embryos were donated at a single clinical IVF centre, on day 5, from 36 patients aged 18-38 years, The data revealed that consumption of glucose and pyruvate, and production of lactate, did not differ between embryos created by IVF or ICSI. Similarly, the mode of insemination did not impact on the triglyceride content of embryos. However, ICSI-derived embryos displayed a more active turnover of amino acids (p=0.023), compared to IVF embryos. The specific amino acids produced in higher quantities from ICSI compared to IVF embryos were aspartate (p=0.016), asparagine (p=0.04), histidine (p=0.021), and threonine (p=0.009) while leucine consumption was significantly lower (p=0.04). However, importantly neither individual nor collective differences in amino acid metabolism were apparent for sibling oocytes subjected to either mode of fertilisation. Embryo morphology (the number of top grade embryos) and development (proportion reaching the blastocyst stage) were comparable in patients undergoing IVF and ICSI. In conclusion, the microinjection of spermatozoa into oocytes does not appear to have an impact on subsequent metabolism and viability. Observed differences in amino acid metabolism may be attributed to male factor infertility of the patients rather than the ICSI procedure per se.

Citation

Sturmey, R. G., & Leary, C. (2020). Metabolic profile of in vitro derived human embryos is not affected by the mode of fertilization. Molecular Human Reproduction, 26(4), 277-287. https://doi.org/10.1093/molehr/gaaa015

• Journal Article Type: Article
• Acceptance Date: Feb 10, 2020
• Online Publication Date: Apr 15, 2020
• Publication Date: Apr 15, 2020
• Deposit Date: Feb 12, 2020
• Publicly Available Date: Apr 16, 2021
• Journal: Molecular Human Reproduction
• Print ISSN: 1360-9947
• Electronic ISSN: 1460-2407
• Publisher: Oxford University Press (OUP)
• Peer Reviewed: Peer Reviewed
• Volume: 26
• Issue: 4
• Pages: 277-287
• DOI: https://doi.org/10.1093/molehr/gaaa015
• Keywords: Blastocyst; Embryo; Human; Metabolism; ICSI, Viability; Metabolism; Fertilization in vitro; Embryo stage 3; Embryo; Fertilization; Sperm injections; Intracytoplasmic
• Public URL: https://hull-repository.worktribe.com/output/3427793
• Publisher URL: https://academic.oup.com/molehr/article-abstract/26/4/277/5736303