The effects of PGS/PGT-A on IVF outcomes Raoul Orvieto M.D. - Department of Obstetrics and Gynecology, Chaim Sheba Medical Center, Ramat Gan, Israel - The Tarnesby-Tarnowski Chair for Family Planning and Fertility Regulation, Sackler Faculty of Medicine, Tel-Aviv University, Israel.
2 Franasiak et al 2014
3
4 (2013)
6
Assumptions Every potentially viable embryo will develop to the blastocyst stage in vitro Mosaicism does not exist in embryos The testing is 100% accurate/precise without false (+)(-) results The biopsy procedure does not reduce the viability of the embryo 7
8 PGS
Technical errors/ mosaicism (2016) 37 blastocyst-stage abnormal embryos from eight patients underwent re-biopsy. 4 embryos were initially analyzed by acgh then with SNP array; 6 of them were initially with SNP array then NGS; 27 of them were initially analyzed by acgh then with NGS. 9/27 (33 %) of embryos originally reported to be aneuploid, upon repeat assessment, were found to be euploid. 9
Technical errors/ mosaicism 11 aneuploidy embryos- re-biopsy - 37 specimens (i) inter-laboratory congruity (ii)intra-embryo congruity of multiple embryo biopsies in a single laboratory Only 2/11 (18.2 %) embryos were identically assessed at two PGS laboratories; 4/11 (36.4 %), on repeat analysis were chromosomally normal, 2 mosaic normal/abnormal, 5/11 (45.5 %) completely differed in reported aneuploidies. In intra-embryo analyses, 5/10 (50 %) differed 10 between biopsy sites.
Technical errors/ mosaicism X 10 (35.7%) of the 28 biopsies (24 trophectoderms and 4 inner cell masses) 11 revealed mosaicism or inconclusive results. 11
Technical errors/ mosaicism One would need a biopsy of 27 cells to assure that the probability of obtaining only euploid cells in a biopsy is less than 5% if the fraction of euploid cells in the embryo is r=0.9 The probability that a biopsy shows no mosaicism as a function of the fraction of euploid cells r = N1/N (N1 is the number of euploid cells, and N the total number of cells) 12
Technical errors/ mosaicism (2017) Biopsies with increased relative DNA content impact clinical outcomes. Possible explanations: Diminished accuracy of the euploid diagnosis, resulting from either technical error or biologic error 13 Mechanical impact of the biopsy itself.
14 Technical errors/ mosaicism
15 False Positive
Technical errors/ mosaicism False Negative X 16
(2016) Abnormal cells within the ICM were significantly more likely to undergo apoptosis than those within the TE. Hence, abnormal TE cells often remained viable, albeit depleted relative to their normal counterparts.? 17
18 PGS
RCT 1 0 outcome- Cumulative live birth rates (fresh+thawed) Screened (PGS) Non-screened Non-screened blastocyst blastocyst cleavage-stage embryo N=100 N=100 N=100 19
(2012) Blastulation rate 47% 0.85 20
RCT 1 0 outcome- Cumulative live birth rates (fresh+thawed) Screened (PGS) Non-screened Non-screened blastocyst blastocyst cleavage-stage embryo N=100 N=100 N=100 Blastulation rate (47%) 47 Blast 47 Blast 100 Cleavage - stage 21
(2017) Reprogenetics (US Labs) database of NGS analyzed embryos. 43%
RCT 1 0 outcome- Cumulative live birth rates (fresh+thawed) Screened (PGS) Non-screened Non-screened blastocyst blastocyst cleavage-stage embryo Blastulation rate (47%) 47 Blast 47 Blast 100 Cleavagestage Euploidy rate (43%) 20.2 Blast 47 Blast 100 Cleavagestage 23
(2013) 65.5% 47.2% 24
50% 28.9% 25
RCT 1 0 outcome- Cumulative live birth rates (fresh+thawed) Screened (PGS) Non-screened Non-screened blastocyst blastocyst cleavage-stage embryo Blastulation rate (47%) 47 Blast 47 Blast 100 Cleavage-stage Euploidy rate (59%) 20.2 Blast 47 Blast 100 Cleavage-stage Sustained implantation rate 65.5% 47.2% 21.5-50% LIVE BIRTHS 13.2% 22.2% 21.5-50% 26
(2012) 45.2% vs 56.0% 27
Donors, average age:25.5 ± 3.03 yrs (range: 19 35 yrs) 28 68%
1 0 outcome- Cumulative live birth rates (fresh+thawed) Screened blastocyst (PGS) Non-screened blastocyst N=10 N=10 13 282 68.98 N=7 N=10 Sustained implantation rate 65.5% 47.2% LIVE BIRTHS N=4.58 N=4.72
(2016) PGS Controls P Cycle (all) All aneuploid embryos No Blastocysts 191 105 26 216 Euploid transfers 60 41/60 (68%) per transfer Age (yrs) 41.7+1.8 39.7+1.3 Clinical intrauterine gestation 21.5% (41/191) 49.5% <0.001 <0.001 41/191 (21.5%) per started cycle LBR 19.9 39.8 <0.001 30
TIME TO PREGNANCY Months/cycles Cycle: OIR OPU (1) 2 3 PGS 65.5% 0 65.5 88.1 Non-PGS 47.2% 47.2 72.1 85.3 100-65.5=34.5 34.5X0.655=22.6 65.5+22.6=88.1 100-47.2= 52.8 52.8X0.472=24.9 47.2+24.9=72.1 100-72.1=27.9 27.9X0.472=13.1 72.1+13.1=85.2 31
Fertil Steril. 2018 Mar;109(3):429-436 Patients participating in the RCT are generally favorably responding subjects who have produced blastocysts for biopsy and analysis. A broader selection of patients with randomization at cycle start rather than blastulation would more appropriately address the applicability of wider use of this technology. The randomized trials were performed in centers with broad and deep experience in embryo biopsy and specimen preparation. The ability to expand these techniques to centers with less experience has yet to be established. The extremely challenging questions of false-positive testing, embryonic damage, and loss of euploid embryos between day 3 and blastulation remain unanswered. 32
Other important considerations about PGT-A that must be addressed by further research include: cost-effectiveness; the role and effect of cryopreservation, time to pregnancy, utility in specific subgroups (such as recurrent loss, prior implantation failure, advanced maternal age, etc.); cumulative success rates over time; and total reproductive potential per intervention. Unfortunately, at the time of this publication, there are currently very few randomized trials registered to elucidate these answers. Large, prospective, well-controlled studies evaluating the combination of multiple approaches (genomics, time-lapse imaging, transcriptomics, proteomics, metabolomics, etc.) At for enhanced present, embryo however, selection applicable there is in insufficient a more inclusive IVF evidence population to are needed recommend to determine not the only routine the effectiveness, use but of also blastocyst the safety and biopsy potential with risks of these technologies. PGT-A aneuploidy will likely be part testing of a future in multidimensional all infertile approach patients. to embryo screening and selection. 33
34 (2018)
THANK YOU 35 35