Preimplantation genetic testing for aneuploidy by microarray analysis of polar bodies in advanced maternal age: a randomized clinical trial.

STUDY QUESTION: Does preimplantation genetic testing for aneuploidy (PGT-A) by comprehensive chromosome screening (CCS) of the first and second polar body to select embryos for transfer increase the likelihood of a live birth within 1 year in advanced maternal age women aged 36-40 years planning an ICSI cycle, compared to ICSI without chromosome analysis? SUMMARY ANSWER: PGT-A by CCS in the first and second polar body to select euploid embryos for transfer does not substantially increase the live birth rate in women aged 36-40 years. WHAT IS KNOWN ALREADY: PGT-A has been used widely to select embryos for transfer in ICSI treatment, with the aim of improving treatment effectiveness. Whether PGT-A improves ICSI outcomes and is beneficial to the patients has remained controversial. STUDY DESIGN, SIZE, DURATION: This is a multinational, multicentre, pragmatic, randomized clinical trial with intention-to-treat analysis. Of 396 women enroled between June 2012 and December 2016, 205 were allocated to CCS of the first and second polar body (study group) as part of their ICSI treatment cycle and 191 were allocated to ICSI treatment without chromosome screening (control group). Block randomization was performed stratified for centre and age group. Participants and clinicians were blinded at the time of enrolment until the day after intervention. PARTICIPANTS/MATERIALS, SETTING, METHODS: Infertile couples in which the female partner was 36-40 years old and who were scheduled to undergo ICSI treatment were eligible. In those assigned to PGT-A, array comparative genomic hybridization (aCGH) analysis of the first and second polar bodies of the fertilized oocytes was performed using the 24sure array of Illumina. If in the first treatment cycle all oocytes were aneuploid, a second treatment with PB array CGH was offered. Participants in the control arm were planned for ICSI without PGT-A. Main exclusion criteria were three or more previous unsuccessful IVF or ICSI cycles, three or more clinical miscarriages, poor response or low ovarian reserve. The primary outcome was the cumulative live birth rate after fresh or frozen embryo transfer recorded over 1 year after the start of the intervention. MAIN RESULTS AND THE ROLE OF CHANCE: Of the 205 participants in the chromosome screening group, 50 (24%) had a live birth with intervention within 1 year, compared to 45 of the 191 in the group without intervention (24%), a difference of 0.83% (95% CI: -7.60 to 9.18%). There were significantly fewer participants in the chromosome screening group with a transfer (relative risk (RR) = 0.81; 95% CI: 0.74-0.89) and fewer with a miscarriage (RR = 0.48; 95% CI: 0.26-0.90). LIMITATIONS, REASONS FOR CAUTION: The targeted sample size was not reached because of suboptimal recruitment; however, the included sample allowed a 90% power to detect the targeted increase. Cumulative outcome data were limited to 1 year. Only 11 patients out of 32 with exclusively aneuploid results underwent a second treatment cycle in the chromosome screening group. WIDER IMPLICATIONS OF THE FINDINGS: The observation that the similarity in birth rates was achieved with fewer transfers, less cryopreservation and fewer miscarriages points to a clinical benefit of PGT-A, and this form of embryo selection may, therefore, be considered to minimize the number of interventions while producing comparable outcomes. Whether these benefits outweigh drawbacks such as the cost for the patient, the higher workload for the IVF lab and the potential effect on the children born after prolonged culture and/or cryopreservation remains to be shown. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by the European Society of Human Reproduction and Embryology. Illumina provided microarrays and other consumables necessary for aCGH testing of polar bodies. M.B.'s institution (UZBrussel) has received educational grants from IBSA, Ferring, Organon, Schering-Plough, Merck and Merck Belgium. M.B. has received consultancy and speakers' fees from Organon, Serono Symposia and Merck. G.G. has received personal fees and non-financial support from MSD, Ferring, Merck-Serono, Finox, TEVA, IBSA, Glycotope, Abbott and Gedeon-Richter as well as personal fees from VitroLife, NMC Healthcare, ReprodWissen, BioSilu and ZIVA. W.V., C.S., P.M.B., V.G., G.A., M.D., T.E.G., L.G., G.Ka., G.Ko., J.L., M.C.M., M.P., A.S., M.T., K.V., J.G. and K.S. declare no conflict of interest. TRIAL REGISTRATION NUMBER: NCT01532284. TRIAL REGISTRATION DATE: 7 February 2012. DATE OF FIRST PATIENT'S ENROLMENT: 25 June 2012.

Oocyte morphology on day 0 correlates with aneuploidy as detected by polar body biopsy and FISH.

PURPOSE: For better selection of oocytes and embryos, preimplantation genetic screening (PGS) was introduced. As from the beginning of IVF, morphology was used as selection criteria; we investigated the combination of both. If there was a correlation between phenotype and genotype, invasive PGS might be replaced. METHOD: Therefore, 104 cycles with PGS were done by biopsy of the first polar body and FISH with five chromosomes. Morphology of the oocyte was recorded digitally and noted for 12 categories in 4-13 values; evaluation of the chromosomes was noted for five chromosomes in five values. Morphology and genetics were correlated to each other. RESULT: Correlations between morphology and genetics for day 0 were found: oocytes with an irregular or dark zona are less probable to have a normal chromosome 13 (80 vs. 53 %, p = 0.001). A medium amount of detritus in the perivitelline space makes it more probable to have a normal chromosome 18 (94 vs. 78 %, p = 0.001). A halo in the cytoplasm makes it less probable to be euploid for chromosome 22 (56 vs. 75 %, p = 0.018). For day 1, pattern "1, 2, 3 and fine" in the pronuclei makes it more probable to be euploid for chromosome 22 (78 vs. 63 %, p = 0.002). CONCLUSION: There are correlations between the oocyte genome and its morphology also on day 0. These correlations are not sufficient to replace PGS.

Sham-controlled implantation after preimplantation genetic screening by polar body biopsy and FISH.

PURPOSE: Preimplantation genetic screening wants to improve artificial reproductive technologies, primarily by raising the rates of pregnancy, implantation and birth. We investigated if embryos derived from oocytes detected euploid for five chromosomes implant better than those which were biopsied but where the genetic detection failed. They were nevertheless transferred, thus serving as a sham control. METHOD: From 2004 to 2008 we performed 104 cycles of PGS with laser biopsy of the first polar body and FISH with five chromosomes. It was offered to all patients with eight or more oocytes, free of charge. The average female age was 36 years. If no euploid oocytes were available, not detected oocytes were transferred. RESULT: In 104 cycles 99 embryo transfers (95 %) were performed, resulting in 28 pregnancies (27 %), 20 births (71 %) and 8 miscarriages (29 %). The implantation rate in the euploid group was 19 vs. 13 % in the not detected group (n.s.). This trend was the same independent of age and embryo morphology. CONCLUSION: The pregnancy rate does not differ significantly from the national average. The trend in better implantation rates of euploid oocytes justifies a continuation of studies in this matter.