Morphokinetic analysis and embryonic prediction for blastocyst formation through an integrated time-lapse system.

OBJECTIVE: To describe the events associated with the blastocyst formation and implantation that occur in embryos during preimplantation development based on the largest sample size ever described with time-lapse monitoring. DESIGN: Observational, retrospective, single-center clinical study. SETTING: University-affiliated private IVF center. PATIENT(S): A total of 7,483 zygotes from 990 first treatments of intracytoplasmic sperm injection (ICSI; 627 of oocyte donor vs. 363 autologous oocyte cycles), of which 832 blastocysts were transferred. INTERVENTION(S): No patient intervention. Embryos were cultured in a time-lapse monitoring system, and the embryos were transferred on day 5 after ICSI. Embryo selection was based on the multivariable model previously developed and on blastocyst morphology. MAIN OUTCOME MEASURE(S): Using a time-lapse system, embryo images were acquired every 15 minutes for 120 hours. Embryos cleavage time points up to the 9-cell stage (t2-t9) as well as to the morula stage (tM) and blastocyst formation (tB) were registered in hours after ICSI. Additionally, duration of the cell cycle and synchrony of the second and third cell cycles were defined. As a result, we have monitored the embryonic development of a total of 3,215 blastocysts, of which 832 were transferred. Finally, we analyzed the characteristics of embryonic development of blastocyst (phase 1) and of implanted and not implanted (phase 2) embryos as finally validated in an independent data set (phase 3). RESULT(S): A detailed retrospective analysis of cleavage times was made for 7,483 zygotes. We analyzed 17 parameters and found several significantly correlated with subsequent blastocyst formation and implantation. The most predictive parameters for blastocyst formation were time of morula formation, tM (81.28-96.0 hours after ICSI), and t8-t5 (≤8.78 hours) or time of transition of 5-blastomere embryos to 8-blastomere embryos with a receiver operating characteristic curve (ROC) value = 0.849 (95% confidence interval [CI], 0.835-0.854; phase 1). These parameters were less predictive of implantation, with a ROC value = 0.546 (95% CI, 0.507-0.585). We also observed that time for expansion blastocyst, tEB (107.9-112.9 hours after ICSI), and t8-t5 (≤5.67 hours after ICSI) predict blastocyst implantation, with a ROC value = 0.591 (95% CI, 0.552-0.630; phase 2). The model was validated on an independent data set and gave a ROC of 0.596 (0.526-0.666; phase 3). CONCLUSION(S): The inclusion of kinetic parameters into score evaluation may improve blastocyst selection criteria and can predict blastocyst formation with high accuracy. We propose two multivariable models based on our findings to classify embryos according to their probabilities of blastocyst stage and implantation in the largest data set ever reported of human blastocysts.

Removal of annexin V-positive sperm cells for intracytoplasmic sperm injection in ovum donation cycles does not improve reproductive outcome: a controlled and randomized trial in unselected males.

OBJECTIVE: To determine the effect of removing presumptive apoptotic sperm cells from samples from unselected males by means of magnetic activated cell sorting (MACS) on live-birth delivery rates after intracytoplasmic sperm injection (ICSI) in couples undergoing ovum donation (OD). DESIGN: Prospective, randomized, triple-blinded, and controlled study. SETTING: Private university-affiliated IVF center. PATIENT(S): A total of 237 infertile couples undergoing ICSI as part of an OD program. INTERVENTION(S): Semen specimens from the control group were prepared by swim-up. Samples from the study group were prepared by swim-up followed by MACS and incubation with annexin V-conjugated microbeads to remove annexin V-positive (AV+) sperm cells. MAIN OUTCOME MEASURE(S): Fertilization rates, morphological features of early embryo development, implantation rates, ongoing pregnancy rates, and live-birth rates. RESULT(S): Similar results were obtained between groups for all the parameters compared: fertilization rates of 75.3% (95% confidence interval [CI], 71.6-78.9) versus 72.1% (95% CI, 68.6-75.7); percentage of good-quality embryos on day 2 of 53.7% (95% CI, 50.3-57.1) versus 51.8% (95% CI, 48.3-55.3) and on day 3 of 54.2% (95% CI, 50.7-57.6) versus 48.9% (95% CI, 45.3-52.4); implantation rates of 42.2% (95% CI, 33.8-48.1) versus 40.1% (95% CI, 34.8-49.6); positive beta-hCG tests of 63.2% (95% CI, 54.7-71.6) versus 68.6% (95% CI, 60.2-76.9), and live-birth rates of 48.4% (95% CI, 39.6-57.1) versus 56.4% (95% CI, 47.3-65.5) in the MACS versus control group. None of the differences reached statistical significance. CONCLUSION(S): Applying MACS technology to remove AV+ sperm cells from unselected males does not improve the reproductive outcome of ICSI in OD.

The human first cell cycle: impact on implantation.

The morphology of fertilization events has been related to successful implantation by subjective criteria (pronuclei score, pronuclei symmetry and position). This work first described these events by time-lapse technology and then compared the timings of fertilization events (second polar body extrusion, first and second pronuclei appearance, abuttal and fading) in implanted versus nonimplanted embryos in a 2-year cohort retrospective study. A total of 1448 transferred embryos from 842 patients undergoing intracytoplasmic sperm injection with oocyte donation were monitored, 212 embryos from treatments where the number of gestational sacs matched the number of transferred embryos and 687 embryos from treatments no biochemical pregnancy was achieved. The timings at which second polar body extrusion (3.3-10.6 h), pronuclear fading (22.2-25.9 h) and length of S-phase (5.7-13.8 h) occurred were linked successfully to embryo implantation. The other parameters were apparently not related, as determined by image acquisition and time-lapse analysis.