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Nagy ZP, Sakkas D, Behr B. Non-invasive assessment of embryo viability by metabolomic profiling of culture media (‘metabolomics’). Reprod Biomed Online 2008; 17:502-7. [DOI: 10.1016/s1472-6483(10)60236-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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53
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Negishi M, Yanaihara A, Iwasaki S, Suzuki N, Hasegawa J, Yorimitsu T, Okai T. Sperm retention site and its influence on pronucleus stage evaluation following intracytoplasmic sperm injection. Reprod Med Biol 2007; 6:171-174. [PMID: 29699274 DOI: 10.1111/j.1447-0578.2007.00181.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Aim: It has been suggested that the position of the sperm after intracytoplasmic sperm injection (ICSI) has an effect on the development and quality of the embryo. In this study, we retrospectively examined whether pronucleus stage evaluation used through clinical studies in recent years has relevance with regard to sperm location. Methods: From 2003 to 2005, 1285 oocytes from 459 patients (average age: 36 years) were retrospectively analyzed. The 459 patients underwent ICSI because of fertilization disorders and oligozoospermia. Follicle stimulation was via either Clomid or the long protocol. Human chorionic gonadotropin was administered to induce ovulation and oocyte retrieval was conducted 35 h later. After confirming the presence of a polar body, we immobilized the ovum at the 6 o'clock position, introduced the injection pipette at the 3 o'clock position and carried out ICSI. Results: When a sperm was located at a position that was opposite to the polar body, both classifications of Scott and Tesarik regarding embryo quality were distinctly low. Furthermore, a good embryo classification ensued when the sperm was located adjacent to the polar body. Conclusion: The zone in which the sperm was located did not always correlate with embryo quality; however, our study suggested that sperm location affects the synchronization of the nucleolus. When carrying out ICSI, it is important to take into consideration the insertion point of the sperm. (Reprod Med Biol 2007; 6: 171-174).
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Affiliation(s)
- Momoko Negishi
- Showa University School of Medicine, Department of Obstetrics and Gynecology, Tokyo, and
| | - Atsushi Yanaihara
- Showa University School of Medicine, Department of Obstetrics and Gynecology, Tokyo, and.,Denentoshi Ladies Clinic, Kanagawa, Japan
| | - Shinji Iwasaki
- Showa University School of Medicine, Department of Obstetrics and Gynecology, Tokyo, and
| | - Norio Suzuki
- Showa University School of Medicine, Department of Obstetrics and Gynecology, Tokyo, and
| | - Junichi Hasegawa
- Showa University School of Medicine, Department of Obstetrics and Gynecology, Tokyo, and
| | | | - Takashi Okai
- Showa University School of Medicine, Department of Obstetrics and Gynecology, Tokyo, and
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Sjöblom P, Menezes J, Cummins L, Mathiyalagan B, Costello MF. Prediction of embryo developmental potential and pregnancy based on early stage morphological characteristics. Fertil Steril 2006; 86:848-61. [PMID: 17027355 DOI: 10.1016/j.fertnstert.2006.03.040] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2005] [Revised: 03/05/2006] [Accepted: 03/05/2006] [Indexed: 10/24/2022]
Abstract
OBJECTIVE To analyze the association between morphological details at different stages of culture with blastocyst development, with an aim to improve selection for transfer. DESIGN Retrospective audit of data. SETTING Tertiary referral center and university hospital. PATIENT(S) Two hundred sixty-eight couples underwent 357 treatment cycles. INTERVENTION(S) Oocyte pickups for IVF or intracytoplasmic sperm injection (ICSI) after ovarian stimulation. Embryos were individually cultured and examined on days 0-2 for morphological details and developmental characteristics, and selected for transfer, freezing, or further culture. MAIN OUTCOME MEASURES The association of blastocyst development and pregnancy with morphological characteristics. RESULT(S) Five morphological characteristics (appearance of the cytoplasm, pronuclei and nucleoli, cytoplasmic deficit, and developmental rate) showed the strongest association with blastocyst development. By combining information from all days of culture into a cumulative score, prediction was greatly improved, compared to only using day 2 morphology. Cytoplasmic dysmorphisms of the oocyte, including accumulation of smooth endoplasmic reticulum, were associated with poor developmental performance. Differential weighting of these characteristics was included in a new embryo scoring system, which showed a strong correlation with implantation. CONCLUSION(S) Weighting individual morphological characteristics of zygotes and embryos and combining them into a cumulative embryo score can improve selection of embryos for transfer.
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Affiliation(s)
- Peter Sjöblom
- School of Women's and Children's Health, University of New South Wales, Australia.
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55
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Taylor TH, Elliott T, Colturato LF, Straub RJ, Mitchell-Leef D, Nagy ZP. Comparison of bovine- and recombinant human-derived hyaluronidase with regard to fertilization rates and embryo morphology in a sibling oocyte model: a prospective, blinded, randomized study. Fertil Steril 2006; 85:1544-6. [PMID: 16647383 DOI: 10.1016/j.fertnstert.2005.10.053] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2005] [Revised: 10/25/2005] [Accepted: 10/25/2005] [Indexed: 10/24/2022]
Abstract
The objective of the present study was to compare a traditionally used bovine-derived hyaluronidase (Hyase) with the newly developed recombinant human-derived enzyme product (Cumulase) in intracytoplasmic sperm injection (ICSI) procedures using a sibling oocyte model in a prospective randomized design. The results of the study demonstrate that Cumulase is safe and effective in an ICSI treatment program and can provide comparable if not improved parameters, including fertilization and embryo developmental rates.
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Affiliation(s)
- Tyl H Taylor
- Reproductive Biology Associates, Atlanta, Georgia 30342, USA
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56
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Arce JC, Ziebe S, Lundin K, Janssens R, Helmgaard L, Sørensen P. Interobserver agreement and intraobserver reproducibility of embryo quality assessments. Hum Reprod 2006; 21:2141-8. [PMID: 16606640 DOI: 10.1093/humrep/del106] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The objective of this investigation was to determine the inter- and intraobserver agreement when assessing embryo quality. METHODS This investigation included 4002 cleaved embryos from 7535 oocytes retrieved in 688 patients undergoing IVF cycles in a multicentre trial. Embryos were evaluated locally at the inverted microscope at 28, 44 and 68 h (+/-1 h) post-insemination. Digital images of the embryos were assessed centrally by three blinded embryologists. To assess reproducibility, 215 randomly selected cleaved embryos from 33 patients were re-evaluated by the three central embryologists. RESULTS The interobserver agreement among the central embryologists (using the same method of evaluation; 2D images) was good for classification of top-quality embryos (kappa 0.71-0.73), excellent for classification of normally developed embryos (kappa 0.83-0.86) and good-excellent for classification of transferable embryos (kappa 0.78-0.82). The interobserver agreement between local and consolidated central assessment (different methods of evaluation, inverted microscopy versus 2D images) was good for all three embryo classifications (kappa 0.64-0.79). The intraobserver reproducibility for all three overall embryo classifications was excellent for the consolidated central assessment (kappa 0.80-0.91). CONCLUSION Embryo quality can be determined with a good degree of interobserver agreement independently of the method of evaluation. Embryologists classify embryos with excellent intraobserver reproducibility.
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Affiliation(s)
- Joan-Carles Arce
- Ferring Pharmaceuticals A/S, Clinical Research and Development, Copenhagen, Denmark.
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57
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Ludwig AK, Werner S, Diedrich K, Nitz B, Ludwig M. The value of pronuclear scoring for the success of IVF and ICSI-cycles. Arch Gynecol Obstet 2005; 273:346-54. [PMID: 16333679 DOI: 10.1007/s00404-005-0102-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2005] [Accepted: 11/11/2005] [Indexed: 10/25/2022]
Abstract
BACKGROUND Pronuclear scoring helps to identify good quality embryos already at the pronuclear stage. There are no data available, however, to demonstrate whether patients benefit from a higher pregnancy rate after pronuclear scoring. METHODS In a retrospective, matched cohort study 338 cycles in which patients chose to score their oocytes at the pronuclear stage (scoring group) were compared with 338 cycles without scoring (control group). The cycles were matched for maternal age, number of previous IVF and ICSI cycles, cryopreservation (yes/no) and diagnosis of primary infertility. RESULTS The pregnancy rate was not significantly different between the scoring group and the control group (24.0 vs. 21.0%, NS) in spite of more cycles with grade A embryos and a higher number of embryos transferred. The presence of a Z1 pronuclear oocyte was found to be associated with the retrieval of more oocytes, a higher fertilization rate and more grade A embryos, as well as a non-significant increase in pregnancy rates (25.1 vs. 18.8%). CONCLUSIONS Benefit from pronuclear scoring seems to be small. Apparently, experienced biologists are able to select "good-quality" pronuclear oocytes in the same way they would do after scoring. However, the results might be biased by differences between the groups.
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Affiliation(s)
- A K Ludwig
- Department of Gynecology and Obstetrics, University Clinic Schleswig-Holstein , Campus Lübeck, Ratzeburger Allee 160, 23538 Lubeck, Germany.
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Payne JF, Raburn DJ, Couchman GM, Price TM, Jamison MG, Walmer DK. Relationship between pre-embryo pronuclear morphology (zygote score) and standard day 2 or 3 embryo morphology with regard to assisted reproductive technique outcomes. Fertil Steril 2005; 84:900-9. [PMID: 16213842 DOI: 10.1016/j.fertnstert.2005.04.047] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2005] [Revised: 04/23/2005] [Accepted: 04/23/2005] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To test the hypothesis that pregnancy rates are low if grade Z1 pre-embryos are not available for transfer and to determine if pronuclear morphology is a better predictor of pregnancy than traditional embryo morphology. DESIGN Prospective clinical study. SETTING Academic human reproduction laboratory. PATIENT(S) One hundred couples undergoing IVF with conventional insemination or ICSI. INTERVENTION(S) Embryo quality was assessed using both pre-embryo pronuclear morphology (zygote scoring or Z-scoring) at the time of fertilization evaluation and standard day 2 and day 3 embryo morphology (number of blastomeres and grading based on degree of fragmentation and blastomere size). MAIN OUTCOME MEASURE(S) We tested two decision models, one based on Z-scores and another on morphology, to determine which grading system better predicted pregnancy outcomes in assisted reproductive technique. Zygote score and embryo morphology were measured for all embryos and the transferred embryo pool. Implantation and pregnancy rates resulting from the embryo transfers of all cycles were calculated. RESULT(S) The Z-score distribution of 552 embryos was 27% Z1, 8% Z2, 50% Z3, and 15% Z4. Z1 and Z3 embryos had significantly (P approximately .03) higher quality over Z2 and Z4 embryos. Using the Z-score decision model with Z1 embryos having highest priority for transfer, pregnancy rates were similar between Z1 and Z3 embryos. Using embryo morphology as a decision model, pregnancy rates were highest in transfers containing one or two "best"-quality embryos. CONCLUSION(S) Z1 and Z3 embryos had similar morphology and pregnancy rates. The decision model based on the Z-score model was not better than standard embryo morphology in predicting pregnancy outcome.
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Affiliation(s)
- John F Payne
- Department of Obstetrics and Gynecology, Duke University Medical Center, Durham, North Carolina 27710, USA
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Senn A, Urner F, Chanson A, Primi MP, Wirthner D, Germond M. Morphological scoring of human pronuclear zygotes for prediction of pregnancy outcome. Hum Reprod 2005; 21:234-9. [PMID: 16126750 DOI: 10.1093/humrep/dei282] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND As embryo selection is not allowed by law in Switzerland, we need a single early scoring system to identify zygotes with high implantation potential and to select zygotes for fresh transfer or cryopreservation. The underlying aim is to maximize the cumulated pregnancy rate while limiting the number of multiple pregnancies. METHODS In all, 613 fresh and 617 frozen-thawed zygotes were scored for proximity, orientation and centring of the pronuclei, cytoplasmic halo, and number and polarization of the nucleolar precursor bodies. From these individual scores, a cumulated pronuclear score (CPNS) was calculated. Correlation between CPNS and implantation was examined and compared between fresh and frozen-thawed zygotes. The effect of freezing on CPNS was also investigated. RESULTS CPNS was positively associated with embryo implantation in both fresh and frozen zygotes. With similar CPNS, frozen zygotes presented implantation rates as high as those of fresh zygotes. Nucleolar precursor bodies pattern and cytoplasmic halo appeared as the most important factors predictive of implantation for both types of zygotes, while pronuclei position was specifically relevant for frozen-thawed zygotes. Freezing induced an alteration of most zygote parameters, resulting in a significantly lower CPNS and a lower pregnancy rate. CONCLUSIONS CPNS may be used as a single prognostic tool for implantation of both fresh and frozen-thawed zygotes. Lower CPNS values of frozen-thawed zygotes may also be indicative of freezing damage to zygotes. Successful implantation of frozen zygotes despite lower CPNS suggests that they may recover after thawing and in vitro culture.
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Affiliation(s)
- Alfred Senn
- Reproductive Medicine Unit, Department of Gynecology and Obstetrics, CHUV, 1011 Lausanne, Switzerland.
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Rienzi L, Ubaldi F, Iacobelli M, Romano S, Minasi MG, Ferrero S, Sapienza F, Baroni E, Greco E. Significance of morphological attributes of the early embryo. Reprod Biomed Online 2005; 10:669-81. [PMID: 15949228 DOI: 10.1016/s1472-6483(10)61676-8] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
There are many morphological transformations during development of human embryos that mainly involve phenomena that can be easily assessed in living embryos by simple non-invasive microscopical observation. A clear correlation between pronuclear morphology and the ability of the resulting embryo to continue developing and to implant has been described. There is also general agreement that a positive relationship exists between early embryo morphology and implantation rate. The parameters classically involved in embryo evaluation are: cleavage rate, blastomere symmetry, cytoplasmic appearance, extent of fragmentation and blastomere nuclear status. In this paper, morphological features that have been related to embryo developmental potential are described. Furthermore, the ability of a cumulative classification scheme developed in the laboratory to predict blastocyst formation and implantation is analysed.
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Affiliation(s)
- Laura Rienzi
- Centre for Reproductive Medicine, European Hospital, Via Portuense 700, 00149 Rome, Italy.
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61
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Abstract
PURPOSE OF REVIEW The present review examines recent publications concerned with the issue of the number of embryos to replace in an in-vitro fertilization cycle and in doing so concentrates on the proposed selection methods that may allow us to transfer one or two embryos. RECENT FINDINGS A number of techniques that will allow us to ascertain the health and viability of the embryo are discussed. These range from methods to assess embryo morphology to those that require more complex forms of technology. Logically the use of the simple methodology is more abundant. However, there is accumulating evidence that some of the more complex assessment techniques may be ready for a more general use. SUMMARY In performing embryo selection we need to develop processes that will be extremely critical, allowing us to limit the number of embryos replaced without detriment to pregnancy rates.
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Affiliation(s)
- Denny Sakkas
- Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, Connecticut 06520-8063, USA.
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Shen Y, Stalf T, Mehnert C, Eichenlaub-Ritter U, Tinneberg HR. High magnitude of light retardation by the zona pellucida is associated with conception cycles. Hum Reprod 2005; 20:1596-606. [PMID: 15734754 DOI: 10.1093/humrep/deh811] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Failures in expression of zona proteins correlate to subfertility in animals. Low expression of the zona proteins by the growing human oocyte may indicate reduced developmental potential. Therefore, we non-invasively analysed the thickness and the structure of the zona pellucida (ZP) of human oocytes with respect to embryo fate after ICSI. METHODS Retardance magnitude and thickness of the inner, middle and outer layers of the ZP were quantitatively analysed by a Polscope in 166 oocytes selected for transfer after ICSI (63 patients; 32.8 +/- 4.4 years) on the basis of pronuclear score at day 1. Blastomere number was determined at day 2. Data were compared between conception cycles (CC; 65 oocytes/23 patients) and non-conception cycles (NCC; 101 oocytes/40 patients) and with respect to maternal age. RESULTS The thickness was slightly elevated (P < 0.001), and the mean magnitude of light retardance was nearly 30% higher (P < 0.001) in the inner layer of the zona pellucida of oocytes contributing to CC compared to NCC. Embryos in the CC group tended to develop faster. CONCLUSIONS The magnitude of light retardance by the zona pellucida inner layer appears to present a unique non-invasive marker for oocyte developmental potential.
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Affiliation(s)
- Y Shen
- Centre of In-Vitro-Fertilisation (CIF) in Justus-Liebig-University, D-35392 Giessen, Germany
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Edirisinghe WR, Jemmott R, Smith C, Allan J. Association of pronuclear Z score with rates of aneuploidy in in vitro-fertilised embryos. Reprod Fertil Dev 2005; 17:529-34. [PMID: 15907278 DOI: 10.1071/rd04065] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2004] [Accepted: 03/31/2005] [Indexed: 11/23/2022] Open
Abstract
The present study aimed to correlate the Z-scoring system to outcomes in in vitro fertilisation (IVF) cycles performed in conjunction with preimplantation genetic diagnosis. In 178 cycles, a total of 468 pronuclear embryos was scored prospectively using the Z score before culture and biopsy on Day 3 to detect chromosomes 13, 16, 18, 21, 22, X and Y. The results showed significant differences between Z1 and Z4 scoring embryos, with Z1 giving an increased biopsy rate (83.3% v. 51.1%), embryo quality (≥fair: 83.3% v. 57.8%) and embryo growth rate (≥six cells: 87.0% v. 44.4%). The incidence of chromosomally normal embryos decreased from Z1 to Z4 (Z1: 40%; Z2: 29.7%; Z3: 22.7%; Z4: 13.6%; P < 0.04). Thus, the Z scoring, mainly Z1 and Z4, correlated significantly with the expected embryo outcomes and preimplantation genetic diagnosis findings. Further improvement of pronuclear scoring with the use of a two-stage assessment is proposed.
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Affiliation(s)
- W R Edirisinghe
- The Wesley IVF Service, The Wesley Hospital, Auchenflower, Qld, Australia.
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64
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Staessen C, Platteau P, Van Assche E, Michiels A, Tournaye H, Camus M, Devroey P, Liebaers I, Van Steirteghem A. Comparison of blastocyst transfer with or without preimplantation genetic diagnosis for aneuploidy screening in couples with advanced maternal age: a prospective randomized controlled trial. Hum Reprod 2004; 19:2849-58. [PMID: 15471934 DOI: 10.1093/humrep/deh536] [Citation(s) in RCA: 433] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND It is generally accepted that the age-related increased aneuploidy rate is correlated with reduced implantation and a higher abortion rate. Therefore, advanced maternal age (AMA) couples are a good target group to assess the possible benefit of preimplantation genetic diagnosis for aneuploidy screening (PGD-AS) on the outcome after assisted reproductive technology (ART). METHODS A prospective randomized controlled clinical trial (RCT) was carried out comparing the outcome after blastocyst transfer combined with PGD-AS using fluorescence in situ hybridization (FISH) for the chromosomes X, Y, 13, 16, 18, 21 and 22 in AMA couples (aged > or =37 years) with a control group without PGD-AS. From the 400 (200 for PGD-AS and 200 controls) couples that were allocated to the trial, an oocyte pick-up was performed effectively in 289 cycles (148 PGD-AS cycles and 141 control cycles). RESULTS Positive serum HCG rates per transfer and per cycle were the same for PGD-AS and controls: 35.8% (19.6%) [%/per embryo transfer (per cycle)] and 32.2% (27.7%), respectively (NS). Significantly fewer embryos were transferred in the PGD-AS group than in the control group (P<0.001). The implantation rate (with fetal heart beat) was 17.1% in the PGD-AS group versus 11.5% in the control group (not significant; P=0.09). We observed a normal diploid status in 36.8% of the embryos. CONCLUSIONS This RCT provides no arguments in favour of PGD-AS for improving clinical outcome per initiated cycle in patients with AMA when there are no restrictions in the number of embryos to be transferred.
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Affiliation(s)
- Catherine Staessen
- Centre for Reproductive Medicine, University Hospital, Dutch-speaking Brussels Free University (Vrije Universiteit Brussel), Laarbeeklaan 101, B-1090 Brussels, Belgium.
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Abstract
Every practitioner active in the field of assisted reproduction treatment is aware of the risks and complications related to twin and higher-order multiple pregnancies. Introduction of single embryo transfer (SET) into IVF/intracytoplasmic sperm injection (ICSI) is one of the possible ways of reducing the rate of twin pregnancy. Careful selection of patients, in combination with elective SET, has been shown to decrease the twin pregnancy rate while maintaining a stable ongoing pregnancy rate. The combination of a woman younger than 38 years of age, in her first or second IVF/ICSI cycle and with an embryo with a high implantation potential is the key to successful SET. This article will discuss embryo selection and patient selection and review the data published on SET. In the Centre for Reproductive Medicine at Middelheim Hospital, 39% of all transfers in 2002 were SET; the ongoing pregnancy rate remained stable at 30.6%. The twin (multiple) pregnancy rate declined to 11.7%. Particular attention should be drawn to the augmenting effect of the pregnancy rate of frozen-thawed cycles. Health economic data available so far subscribe the plea for SET.
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Affiliation(s)
- Diane De Neubourg
- Centre for Reproductive Medicine, Middelheim Hospital, Lindendreef 1, B-2020 Antwerp, Belgium.
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