Ali Ahmady

Evaluation of post-thaw DNA integrity of mouse blastocysts after ultrarapid and slow freezing

OBJECTIVE To evaluate the effect of vitrification and two other methods of slow cryopreservation on DNA integrity in expanded and nonexpanded blastocysts. DESIGN Prospective in vitro study. SETTING Tertiary care academic hospital. INTERVENTION(S) 1) Twenty-two expanded blastocysts (EB) and 17 nonexpanded blastocysts (NEB) vitrified in cryotips; 2) 15 EB and 16 NEB by slow freezing using propanediol; 3) 11 EB and 16 NEB by slow cryopreservation using glycerol; and 4) 14 EB and 13 NEB as fresh control samples. MAIN OUTCOME MEASURE(S) DNA fragmentation by TUNEL and confocal imaging. RESULT(S) Blastocysts slowly cryopreserved with glycerol showed DNA integrity of 94.76 +/- 4.70% and 90.87 +/- 6.16% for NEB and EB, respectively. Propanediol cryopreservation showed values of 72.63 +/- 13.44% and 56.19 +/- 25.49% and vitrification 84.36 +/- 8.7%6 and 77.61 +/- 16.65%, respectively, for the same groups. The NEB showed less DNA fragmentation than EB in all cryopreservation techniques, but this was significant only with slow freezing using propanediol. CONCLUSION(S) All cryopreservation techniques induce DNA damage to blastocysts. Damage is maximal with propanediol and minimal with slow freezing using glycerol. The more expanded the blastocyst, the greater is the susceptibility to DNA damage during cryopreservation.

Pushing the limits of detection: investigation of cell-free DNA for aneuploidy screening in embryos

OBJECTIVE To determine the accuracy of cell-free DNA (cfDNA) in spent embryo medium (SEM) for ploidy and sex detection at the cleavage and blastocyst stages. To determine if assisted hatching (AH) and morphologic grade influence cfDNA concentration and accuracy. DESIGN Prospective cohort. SETTING Academic fertility center. PATIENT(S) Nine patients undergoing IVF; 41 donated two-pronuclei embryos and 20 embryos from patients undergoing preimplantation genetic testing for aneuploidy (PGT-A). INTERVENTIONS(S) In a donated embryo arm, SEM was collected on days 3 and 5, with one-half of the embryos undergoing AH before and one-half after. In a clinical arm, SEM was collected on day 5 before trophectoderm (TE) biopsy. Samples underwent PGT-A with the use of next-generation sequencing. cfDNA results were compared with corresponding whole embryos and TE biopsies. MAIN OUTCOME MEASURE(S) Concordance rates, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for ploidy and sex detection with the use of cfDNA. RESULT(S) Of 141 samples, cfDNA was amplified in 39% and 80.4% of days 3 and 5 SEM, respectively. Concordances for ploidy and sex, respectively, were 56.3% and 81.3% between day 3 cfDNA and whole embryos, and 65% and 70% between day 5 cfDNA and TE biopsies. Day 5 cfDNA sensitivity and specificity for aneuploidy were 0.8 and 0.61, respectively. PPV and NPV were 0.47 and 0.88, respectively. Timing of AH and morphology did not influence cfDNA concentration or accuracy. CONCLUSION(S) cfDNA is detectable on days 3 and 5, but more accurate on day 5. Although our data suggest moderate concordance rates, PGT-A with the use of cfDNA must be further optimized before clinical implementation.

Micro-RNAs involved in cellular proliferation have altered expression profiles in granulosa of young women with diminished ovarian reserve

PurposeThe study aims to determine differences in micro-RNA (miRNA) expression in granulosa (GC) and cumulus cells (CC) between young women with diminished ovarian reserve (DOR) or normal ovarian reserve (NOR). Secondary objective was to identify downstream signaling pathways that could ultimately indicate causes of lower developmental competence of oocytes from young women with DOR.MethodsThe method of the study is prospective cohort study.ResultsOf the miRNA, 125 are differentially expressed in GC between DOR and NOR. Only nine miRNA were different in CC; therefore, we focused analysis on GC. In DOR GC, miR-100-5p, miR-16-5p, miR-30a-3p, and miR-193a-3p were significantly downregulated, while miR-155-5p, miR-192-5p, miR-128-3p, miR-486-5p, miR130a-3p, miR-92a-3p, miR-17-3p, miR-221-3p, and miR-175p were increased. This pattern predicted higher cell proliferation in the DOR GC. The primary pathways include MAPK, Wnt, and TGFbeta.ConclusionsThe miRNA pattern identified critical functions in cell proliferation and survival associated with DOR. GC in women with DOR seems to respond differently to the LH surge.

Blastulation timing is associated with differential mitochondrial content in euploid embryos

PurposePreimplantation genetic screening (PGS) and assessment of mitochondrial content (MC) are current methods for selection of the best embryos for transfer. Studies suggest that time-lapse morphokinetics (TLM) may also be helpful for selecting embryos more likely to implant. In our study, we sought to examine the relationship between TLM parameters and MC to determine if they could be used adjunctively in embryo selection. We also examined the relationship between MC with ploidy and blastulation.MethodsCryopreserved human embryos at the zygote stage were thawed and cultured in a time-lapse system. Blastomere and trophectoderm biopsies were performed on days 3 and 6. Biopsied cells and all whole embryos from day 6 were analyzed for MC (ratio of mitochondrial to nuclear DNA) and ploidy using next-generation sequencing.ResultsIn embryos, MC per cell declined between day 3 and day 6. While early cleavage parameters did not predict MC, embryos with longer blastulation timing had higher MC on day 6. Day 6 MC was lower in euploid vs. aneuploid embryos and lower in blastocysts vs. arrested embryos.ConclusionsA lower MC at the blastocyst stage was associated with euploid status and blastocyst formation, indicating better embryo quality compared to those with a higher MC. Higher MC in aneuploid and arrested embryos may be explained by slower cell division or degradation of genomic DNA over time. Blastulation timing may be helpful for selection of higher quality embryos. Combining blastulation timing and MC along with morphologic grading and euploid status may offer a new direction in embryo selection.