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The Questionable Efficacy of Aneuploid Screening in Preimplantation Genetic Diagnosis
cumulative contribution of endometrial coculture (EC) in such cases undergoing preimplantation genetic diagnosis (PGD). DESIGN: Retrospective Study MATERIALS AND METHODS: Overall, 113 cycles in which PGD with the indication of recurrent implantation failure (nⱖ3) have been performed were included in the study between March 2001 and November 2004. Patients were retrospectively grouped according to culture media systems used. In 78 patients (group I) sequential media has been of choice throughout the culture period and in 35 cycles endometrial coculture has been utilized. From pre-zygote stage to embryo transfer, daily embryo growth parameters were scored and compared between groups. Blastomere biopsy was performed either on day 3 or day 4 and normal embryos after FISH analysis were selected for embryo transfer. RESULTS: No statistically significant difference in main patient and cycle parameters such as female age, male age, BMI, gonadotrophine ampoules used, MII oocytes collected and fertilized were found between groups (p⬎0.05). However, when embryo development characteristics were compared, faster cleavage on day 3 (74,8%) and improved viability with lower arrest rate after biopsy (14.6%) were observed in coculture group with respect to conventional culture media (62.4% and 21.7% respectively). Embryo growth and quality were also superior in endometrial coculture in comparison to previous cycles with conventional media in the same group of patients. CONCLUSION: Our results show that culturing embryos on endometrial monolayer cells seems to increase the cleavage rate and the quality of embryos in recurrent implantation failure cases. Furthermore, since increase in cleavage rate can also increase the number of embryos available for biopsy during preimplantation genetic diagnosis, culturing the embryos in endometrial coculture systems can improve the cycle outcome. Therefore, EC can be a successful alternative to conventional culture media in such cases where PGD is planned. Supported by: None
P-534 Chromosome Analysis in Supernumerary Embryos Obtained From Patients Undergoing Aneuploidy Screening for Repeated Implantation Failure or Recurrent Miscarriage. A. Ao, S. Jin, S. Tan. McGill University, Montreal, PQ, Canada. OBJECTIVE: To assess the prevalence and types of chromosome abnormality in spare preimplantation embryos from women with repeated IVF failure (RIF) or with unexplained recurrent miscarriage (RM) undergoing preimplantation genetic diagnosis for aneuploidy screening (PGD-AS). DESIGN: Analysis of chromosome abnormality in embryos from a single center MATERIALS AND METHODS: A total of 434 normally fertilized embryos were analyzed for chromosome abnormality following day 3 embryo biopsy for patients either with repeated IVF failure (RIF) or with unexplained recurrent miscarriage (RM). The difference in the mean maternal age between these two groups of patients was not statistically significant. A total of 140 embryos that were not selected for transfer to patients after the genetic diagnosis were analyzed for chromosome abnormalities using multi-color fluorescence in situ hybridization (FISH) DNA probes, specific for 7 to 8 different chromosomes (X,Y, 13, 15, 16, 18, 21, 22). RESULTS: A total of 261 embryos from 18 RIF patients with a mean age (⫾SD) of 40.4 ⫾2.5 and 125 embryos from 10 RM patients with a mean age of 38⫾4.5 were tested for chromosome abnormality following PGD-AS. The overall chromosome abnormality on day 3 diagnoses for patients with RIF and RM were 63.7% and 54% respectively, the difference was not statistically significant. The most common form of chromosome abnormality based on single cell diagnosis in both groups was aneuploid (32.7%) followed by chaotic (25%), polyploid (1.9%) and haploid (1%). The most prevalent aneuploidy observed in both groups of patients was chromosome 16 (20%) followed by chromosomes 22 (19%), 13 (18%) and 21 (16%). A total of 137 supernumerary embryos from RIF and 61 embryos from RM patients were analyzed for chromosome abnormality. In these embryos, mosaicism was observed in 34% of the embryos followed by aneuploid (26.2%), chaotic (14.6%), polyploid (3.5%) and haploid (0.5%). Similar to day 3 diagnosis, chromosome 16 was the most common form of aneuploidy (23%) observed in these spare embryos. CONCLUSION: In our study group, we did not find any difference in the overall rate of chromosome abnormality between RIF and RM patients. Further investigations with larger number of embryos are needed to evaluate
FERTILITY & STERILITY威
whether there is any difference in the rate and type of chromosome abnormality between these two groups of patients. Supported by: None
P-535 The Questionable Efficacy of Aneuploid Screening in Preimplantation Genetic Diagnosis. C. B. Coulam, R. S. Jeyendran, E. Pergament. Center for Pregnancy Success, Chicago, IL; Andrology Laboratory Services, Chicago, IL; Northwestern Reproductive Genetics, Chicago, IL. OBJECTIVE: A paradox currently exists with regard to preimplantation diagnosis (PGD) of aneuploidy: human embryos have extremely high rates of chromosome abnormalities and therefore many IVF programs are offering aneuploid screening. However, these embryos also have extremely high rates of chromosome mosaicism, which raises the question of the efficacy of aneuploid screening. A review of more than a dozen publications indicated that decisions to transfer embryos were almost exclusively based on aneuploid screening of a single blastomere. To determine the validity of such decision making, we investigated the rates of concordance between two blastomeres derived from one preimplantation embryo following aneuploid screening for chromosomes 13, 15, 16, 18, 21, 22, X and Y. DESIGN: Fluorescent in situ hybridization (FISH) study comparing 2 blastomeres from the same embryo. Prospective bservational study. MATERIALS AND METHODS: Two blastomeres were successfully removed from 167 embryos on day 3, out of 287 embryos obtained from 29 patients. FISH analysis was successful on both blastomeres for 109 embryos and screened for aneuploidy of chromosomes 13, 15, 16, 18, 21, 22, X and Y. The FISH results of the 2 blastomeres from the same embryo were compared. RESULTS: Of the 109 embryos, 27 (24.8%) were concordant for the FISH analysis and 82 (75.2%) were discordant. When individual chromosomes were studies among the embryos with discordant results, 82% (170/ 207) had one blastomere identified as euploid and one as aneuploid. Of the discordances having the potential of involving live born with birth defects 30.5% (25/82) of the embryos involved a trisomy/disomy pairing for chromosomes 13, 18, 21 and X. CONCLUSION: The high incidence of discordance between blastomeres obtained from preimplantation embryos considerably reduces the likelihood that aneuploid screening to improve the IVF outcome. The questionable validity of PGD based on FISH analysis of one blastomere supports the need for a randomized, multicenter trial before aneuploid screening becomes a clinically accepted approach. Supported by: None
P-536 The Identification of a Dicentric X-chromosome in Embryos Undergoing PGD for Aneuploidy Screening in a Couple With Normal Karyotypes and Eight Previous Losses. W. G. Kearns, R. Pen, J. Kaminsky, L. Timmreck, S. F. Hoegerman. Shady Grove Center for Preimplantation Genetics, Rockville, MD; Shady Grove Fertility Reproductive Science Center, Rockville, MD; The College of William and Mary, Williamsburg, VA. OBJECTIVE: To perform in vitro fertilization (IVF) and preimplantation genetic diagnosis (PGD) for aneuploidy screening in a couple with recurrent losses. DESIGN: Case report MATERIALS AND METHODS: A 38 year-old woman with a history of ulcerative colitis and recurrent pregnancy loss presented for IVF and PGD for aneuploidy. The patient has one living child and eight pregnancy losses. Both the patient and her 39 year-old husband have normal karyotypes, and he has abnormal semen parameters. Laser assisted embryo biopsy was performed on 6 day-3 cleaving embryos. Cell lysis, fixation, hybridization, and stringency washes were performed according to routine laboratory protocols. Multi-color fluorescence in situ hybridization (FISH) was used to determine aneuploidy for chromosomes 13, 14, 15, 16, 17, 18, 21, 22, X and Y. RESULTS: Five of 6 embryos were aneuploid. Three embryos were aneuploid for 2 different chromosomes, one was abnormal for 3 chromosomes and one embryo was abnormal for 4 separate chromosomes. Two of 6 embryos had X chromosome fluorescent signals consistent for the presence of a dicentric chromosome. Therefore, we used telomere FISH probes
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P-534 Chromosome Analysis in Supernumerary Embryos Obtained From Patients Undergoing Aneuploidy Screening for Repeated Implantation Failure or Recurrent Miscarriage. A. Ao, S. Jin, S. Tan. McGill University, Montreal, PQ, Canada. OBJECTIVE: To assess the prevalence and types of chromosome abnormality in spare preimplantation embryos from women with repeated IVF failure (RIF) or with unexplained recurrent miscarriage (RM) undergoing preimplantation genetic diagnosis for aneuploidy screening (PGD-AS). DESIGN: Analysis of chromosome abnormality in embryos from a single center MATERIALS AND METHODS: A total of 434 normally fertilized embryos were analyzed for chromosome abnormality following day 3 embryo biopsy for patients either with repeated IVF failure (RIF) or with unexplained recurrent miscarriage (RM). The difference in the mean maternal age between these two groups of patients was not statistically significant. A total of 140 embryos that were not selected for transfer to patients after the genetic diagnosis were analyzed for chromosome abnormalities using multi-color fluorescence in situ hybridization (FISH) DNA probes, specific for 7 to 8 different chromosomes (X,Y, 13, 15, 16, 18, 21, 22). RESULTS: A total of 261 embryos from 18 RIF patients with a mean age (⫾SD) of 40.4 ⫾2.5 and 125 embryos from 10 RM patients with a mean age of 38⫾4.5 were tested for chromosome abnormality following PGD-AS. The overall chromosome abnormality on day 3 diagnoses for patients with RIF and RM were 63.7% and 54% respectively, the difference was not statistically significant. The most common form of chromosome abnormality based on single cell diagnosis in both groups was aneuploid (32.7%) followed by chaotic (25%), polyploid (1.9%) and haploid (1%). The most prevalent aneuploidy observed in both groups of patients was chromosome 16 (20%) followed by chromosomes 22 (19%), 13 (18%) and 21 (16%). A total of 137 supernumerary embryos from RIF and 61 embryos from RM patients were analyzed for chromosome abnormality. In these embryos, mosaicism was observed in 34% of the embryos followed by aneuploid (26.2%), chaotic (14.6%), polyploid (3.5%) and haploid (0.5%). Similar to day 3 diagnosis, chromosome 16 was the most common form of aneuploidy (23%) observed in these spare embryos. CONCLUSION: In our study group, we did not find any difference in the overall rate of chromosome abnormality between RIF and RM patients. Further investigations with larger number of embryos are needed to evaluate
FERTILITY & STERILITY威
whether there is any difference in the rate and type of chromosome abnormality between these two groups of patients. Supported by: None
P-535 The Questionable Efficacy of Aneuploid Screening in Preimplantation Genetic Diagnosis. C. B. Coulam, R. S. Jeyendran, E. Pergament. Center for Pregnancy Success, Chicago, IL; Andrology Laboratory Services, Chicago, IL; Northwestern Reproductive Genetics, Chicago, IL. OBJECTIVE: A paradox currently exists with regard to preimplantation diagnosis (PGD) of aneuploidy: human embryos have extremely high rates of chromosome abnormalities and therefore many IVF programs are offering aneuploid screening. However, these embryos also have extremely high rates of chromosome mosaicism, which raises the question of the efficacy of aneuploid screening. A review of more than a dozen publications indicated that decisions to transfer embryos were almost exclusively based on aneuploid screening of a single blastomere. To determine the validity of such decision making, we investigated the rates of concordance between two blastomeres derived from one preimplantation embryo following aneuploid screening for chromosomes 13, 15, 16, 18, 21, 22, X and Y. DESIGN: Fluorescent in situ hybridization (FISH) study comparing 2 blastomeres from the same embryo. Prospective bservational study. MATERIALS AND METHODS: Two blastomeres were successfully removed from 167 embryos on day 3, out of 287 embryos obtained from 29 patients. FISH analysis was successful on both blastomeres for 109 embryos and screened for aneuploidy of chromosomes 13, 15, 16, 18, 21, 22, X and Y. The FISH results of the 2 blastomeres from the same embryo were compared. RESULTS: Of the 109 embryos, 27 (24.8%) were concordant for the FISH analysis and 82 (75.2%) were discordant. When individual chromosomes were studies among the embryos with discordant results, 82% (170/ 207) had one blastomere identified as euploid and one as aneuploid. Of the discordances having the potential of involving live born with birth defects 30.5% (25/82) of the embryos involved a trisomy/disomy pairing for chromosomes 13, 18, 21 and X. CONCLUSION: The high incidence of discordance between blastomeres obtained from preimplantation embryos considerably reduces the likelihood that aneuploid screening to improve the IVF outcome. The questionable validity of PGD based on FISH analysis of one blastomere supports the need for a randomized, multicenter trial before aneuploid screening becomes a clinically accepted approach. Supported by: None
P-536 The Identification of a Dicentric X-chromosome in Embryos Undergoing PGD for Aneuploidy Screening in a Couple With Normal Karyotypes and Eight Previous Losses. W. G. Kearns, R. Pen, J. Kaminsky, L. Timmreck, S. F. Hoegerman. Shady Grove Center for Preimplantation Genetics, Rockville, MD; Shady Grove Fertility Reproductive Science Center, Rockville, MD; The College of William and Mary, Williamsburg, VA. OBJECTIVE: To perform in vitro fertilization (IVF) and preimplantation genetic diagnosis (PGD) for aneuploidy screening in a couple with recurrent losses. DESIGN: Case report MATERIALS AND METHODS: A 38 year-old woman with a history of ulcerative colitis and recurrent pregnancy loss presented for IVF and PGD for aneuploidy. The patient has one living child and eight pregnancy losses. Both the patient and her 39 year-old husband have normal karyotypes, and he has abnormal semen parameters. Laser assisted embryo biopsy was performed on 6 day-3 cleaving embryos. Cell lysis, fixation, hybridization, and stringency washes were performed according to routine laboratory protocols. Multi-color fluorescence in situ hybridization (FISH) was used to determine aneuploidy for chromosomes 13, 14, 15, 16, 17, 18, 21, 22, X and Y. RESULTS: Five of 6 embryos were aneuploid. Three embryos were aneuploid for 2 different chromosomes, one was abnormal for 3 chromosomes and one embryo was abnormal for 4 separate chromosomes. Two of 6 embryos had X chromosome fluorescent signals consistent for the presence of a dicentric chromosome. Therefore, we used telomere FISH probes
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