REVIEW  HOT TOPICS IN HUMAN ASSISTED REPRODUCTION: PERFECTING THE ART OF ART 

Panminerva Medica 2022 June;64(2):171-84

DOI: 10.23736/S0031-0808.22.04680-8

Copyright © 2022 EDIZIONI MINERVA MEDICA

language: English

Oocyte quality and embryo selection strategies: a review for the embryologists, by the embryologists

Christina ANAGNOSTOPOULOU ¹, Israel MALDONADO ROSAS ², Neha SINGH ³, Nivita GUGNANI ⁴, Annapoorani CHOCKALINGHAM ⁵, Keerti SINGH ⁶, Dimple DESAI ⁷, Mahsa DARBANDI ^{8, 9}, Madhumitha MANOHARAN ¹⁰, Sara DARBANDI ^{8, 9}, Sofia I. LEONARDI DIAZ ¹¹, Sajal GUPTA ¹², Ralf HENKEL ^{12, 13, 14, 15}, Hassan N. SALLAM ¹⁶, Florence BOITRELLE ^{17, 18}, Kelly A. WIRKA ¹⁹, Ashok AGARWAL ¹² ✉

¹ Unit Reproductive Medicine, Embryo ART, Lito Maternity Hospital, Athens, Greece; ² Citmer Reproductive Medicine, IVF LAB, Mexico City, Mexico; ³ NOVA IVF, Gorakhpur, India; ⁴ Milann - The Fertility Center, New Delhi, India; ⁵ Gene2Genome, Jacksonville, FL, USA; ⁶ Faculty of Medical Sciences, The University of the West Indies - Cave Hill Campus, Bridgetown, Barbados; ⁷ DPU IVF and Endoscopy Center, Dr. D.Y. Patil Hospital and Research Center, Pune, India; ⁸ Fetal Health Research Center, Hope Generation Foundation, Tehran, Iran; ⁹ Gene Therapy and Regenerative Medicine Research Center, Hope Generation Foundation, Tehran, Iran; ¹⁰ AlphaLife Fertility and Women’s Center, Salem, India; ¹¹ Maternal and Child Public Hospital, Salta, Argentina; ¹² American Center for Reproductive Medicine, Cleveland, OH, USA; ¹³ Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK; ¹⁴ Department of Medical Bioscience, University of the Western Cape, Bellville, South Africa; ¹⁵ LogixX Pharma, Theale, UK; ¹⁶ Department of Obstetrics and Gynecology, Faculty of Medicine, Alexandria University, Alexandria, Egypt; ¹⁷ Unit of Reproductive Biology, Fertility Preservation, Andrology, CECOS, Hospital of Poissy, Poissy, France; ¹⁸ Department of Biology, Reproduction, Epigenetics, Environment and Development, Paris-Saclay University, UVSQ, INRAE, BREED, Jouy-en-Josas, France; ¹⁹ Unit of Fertility and Endocrinology, Medical Affairs, EMD Serono, Rockland, MA, USA

With the advance of assisted reproduction techniques, and the trend towards blastocyst culture and single embryo transfer, gamete and embryo assessment have gained greater importance in ART treatment. Embryo quality depends mainly on gamete quality and culture conditions. Oocyte maturity identification is necessary in order to plan fertilization timing. Mature oocytes at the metaphase II stage show a higher fertilization rate compared to immature oocytes. Morphology assessment is a critical yet challenging task that may serve as a good prognostic tool for future development and implantation potential if done effectively. Various grading systems have been suggested to assess embryos at pronuclear, cleavage, and blastocyst stages. By identifying the embryo with the highest implantation potential, it is possible to reduce the number of embryos transferred without compromising the chances of a successful pregnancy. Apart from the conventional morphology assessment, there are several invasive or non-invasive methods for embryo selection such as preimplantation genetic testing, morphokinetics, proteomics, metabolomics, oxygen consumption, and measurement of oxidative stress in culture medium. Morphokinetics is a method based on time-lapse technology and continuous monitoring of embryos. In this review, we aimed to describe and compare the most effective and widely used methods for gamete and embryo assessment as well as embryo selection.

KEY WORDS: Fertilization in vitro; Oocytes; In vitro oocyte maturation techniques; Microscopy