Time-lapse deselection model for human day 3 in vitro fertilization embryos: the combination of qualitative and quantitative measures of embryo growth.

OBJECTIVE: To present a time-lapse deselection model involving both qualitative and quantitative parameters for assessing embryos on day 3.

DESIGN: Retrospective cohort study and prospective validation.

SETTING: Private IVF center.

PATIENT(S): A total of 270 embryos with known implantation data (KID) after day 3 transfer from 212 IVF/intracytoplasmic sperm injection (ICSI) cycles were retrospectively analyzed for building the proposed deselection model, followed by prospective validation using an additional 66 KID embryos.

INTERVENTION(S): None.

MAIN OUTCOME MEASURE(S): Morphological score on day 3, embryo morphokinetic parameters, abnormal cleavage patterns, and known implantation results.

RESULT(S): All included embryos were categorized either retrospectively or prospectively into 7 grades (A+, A, B, C, D, E, F). Qualitative deselection parameters included poor conventional day 3 morphology, abnormal cleavage patterns identified via time-lapse monitoring, and <8 cells at 68 hours postinsemination. Quantitative parameters included time from pronuclear fading (PNF) to 5-cell stage and duration of 3-cell stage. KID implantation rates of embryos graded from A+ to F were 52.9%, 36.1%, 25.0%, 13.8%, 15.6%, 3.1%, and 0 respectively (area under the curve [AUC] = 0.762; 95% confidence interval [CI], 0.701-0.824), and a similar pattern was seen in either IVF (AUC = 0.721; 95% CI, 0.622-0.821) or ICSI embryos (AUC = 0.790; 95% CI, 0.711-0.868). Preliminary prospective validation using 66 KID embryos also showed statistically significant prediction in Medicult (AUC = 0.750; 95% CI, 0.588-0.912) and Vitrolife G-Series (AUC = 0.820; 95% CI, 0.671-0.969) suites of culture media.

CONCLUSION(S): The proposed model involving both qualitative and quantitative deselection effectively predicts day 3 embryo implantation potential and is applicable to all IVF embryos regardless of insemination method by using PNF as the reference starting time point.