Cross-validation and predictive value of near-infrared spectroscopy algorithms for day-5 blastocyst transfer

Near-infrared (NIR) spectroscopic metabolomic profiling of spent embryo-culture media has been used to calculate a viability score for individual embryos. These scores have been found to correlate to the reproductive potential of cleavage-stage embryos. In this study, 137 spent blastocyst media samples were collected after single-embryo transfer and analysed by NIR spectroscopy to generate an algorithm and calculate viability scores. To blindly validate the algorithm development process, another algorithm was trained on 47 preselected samples from clinic 1 and then used to predict the outcome of 42 samples from clinic 2. The overall pregnancy rate from the two clinical sites was 50.4%. A positive correlation (R-2 = 0.82, P = 0.03) was observed with the increasing viability score quintiles and their associated implantation rates. Cross-validation of an algorithm generated from NIR analysis of media samples at one clinical setting blindly was shown to predict implantation potential of blastocysts cultured at another clinic in a different culture media and culture volume. This study demonstrates that metabolomic profiling by NIR spectroscopic analysis of day-5 spent embryo-culture media can predict the implantation potential of blastocysts. Furthermore, this method may not be restricted to a specific set of culturing conditions. (C) 2011, Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.