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Catherine Staessen

Publications and source records attributed to Catherine Staessen.

8 recordsLinked to original sources
PubMed2006

The analysis of one or two blastomeres for PGD using fluorescence in-situ hybridization.

BACKGROUND: The analysis of one or two blastomeres for PGD using fluorescence in-situ hybridization (FISH) is debated. The proportion of analysable embryos, false negatives, false positives, sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV) and efficiency were evaluated when one or two blastomeres were analysed. METHODS: Embryos of patients having PGD for aneuploidy screening were assigned non-randomly to two groups: group I (n = 413), more slow cleaving embryos with one nucleus for analysis, and group II (n = 1366), regularly cleaving embryos with two nuclei for analysis. A two-round FISH procedure was performed investigating seven chromosomes; 486 embryos were reanalysed. RESULTS: The proportion of analysable embryos was significantly higher in group II (98.2 versus 95.9%) (P = 0.04). Despite the apparently increased false-positive rate (group I: 25.6% and group II: 13.6%) and the decreased PPV (group I: 91.9% and group II: 96.7%), specificity (group I: 74.4% and group II: 86.4%) and efficiency (group I: 93.5% and group II: 97.3%) in group I, no significance was reached (P = 0.11, P = 0.053, P = 0.11 and P = 0.06, respectively). CONCLUSIONS: Although the analysis of one blastomere generates statistically significantly fewer embryos with a diagnosis than does the analysis of two blastomeres, the 2% difference may not be clinically relevant. The diagnostic accuracy is not significantly different between the two groups, hence not favouring the analysis of one or two blastomeres.

Aneuploidy↗
PubMed2006

Single-cell chromosomal imbalances detection by array CGH.

Genomic imbalances are a major cause of constitutional and acquired disorders. Therefore, aneuploidy screening has become the cornerstone of preimplantation, prenatal and postnatal genetic diagnosis, as well as a routine aspect of the diagnostic workup of many acquired disorders. Recently, array comparative genomic hybridization (array CGH) has been introduced as a rapid and high-resolution method for the detection of both benign and disease-causing genomic copy-number variations. Until now, array CGH has been performed using a significant quantity of DNA derived from a pool of cells. Here, we present an array CGH method that accurately detects chromosomal imbalances from a single lymphoblast, fibroblast and blastomere within a single day. Trisomy 13, 18, 21 and monosomy X, as well as normal ploidy levels of all other chromosomes, were accurately determined from single fibroblasts. Moreover, we showed that a segmental deletion as small as 34 Mb could be detected. Finally, we demonstrated the possibility to detect aneuploidies in single blastomeres derived from preimplantation embryos. This technique offers new possibilities for genetic analysis of single cells in general and opens the route towards aneuploidy screening and detection of unbalanced translocations in preimplantation embryos in particular.

Aneuploidy↗
PubMed2006

The importance of aneuploidy screening in reciprocal translocation carriers.

The purpose of this study is to investigate the aneuploidy rate and the mosaicism of chromosomes not involved in reciprocal translocations. Aneuploidy screening (AS) (13, 16, 18, 21 and 22) was performed as a re-analysis on fixed blastomeres from 126 embryos already analysed in preimplantation genetic diagnosis (PGD) cycles of eight female and five male reciprocal translocation carriers who had not achieved a pregnancy. A successful diagnosis for AS was achieved in 91.3% of embryos; 30.9% were euploid and 60.3% were aneuploid for the five chromosomes analysed. Of the embryos, 8.7% were euploid for AS and normal-balanced for the translocation and 22.2% were euploid for AS but unbalanced for the translocation; 8% of the embryos were aneuploid for AS but normal-balanced for the translocation and 52.4% were aneuploid for AS and also unbalanced for the translocation. At least 58.7% of the embryos were mosaic regarding mosaicism for the chromosomes involved and not involved in the translocations. Six of the 16 embryos transferred in the PGD cycles were aneuploid for the AS study; four of them were also mosaics. AS should be performed in reciprocal translocation carriers after segregation analysis in PGD.

Aneuploidy↗
PubMed2005

Preimplantation genetic diagnosis for aneuploidy screening in patients with unexplained recurrent miscarriages.

OBJECTIVE: To determine the aneuploidy rate in embryos of women with idiopathic recurrent miscarriages and to evaluate whether preimplantation genetic diagnosis for aneuploidy screening could be a feasible approach to improve the possibility of successful pregnancy in these couples. DESIGN: Prospective cohort study. SETTING: Tertiary university referral center. PATIENT(S): Women (n = 49) with recurrent idiopathic miscarriages. INTERVENTION(S): In vitro fertilization with preimplantation genetic diagnosis for aneuploidy screening. MAIN OUTCOME MEASURE(S): Ongoing pregnancy rate (PR) and aneuploidy rate. RESULT(S): The aneuploidy rate was, respectively, 43.85% and 66.95% in the younger and older group. The ongoing PR per cycle was 25.71% in the younger and 2.94% in the older patients. CONCLUSION(S): There is no therapeutic evidence to prescribe IVF with or without preimplantation genetic diagnosis for aneuploidy screening for this heterogeneous group of patients.

Abortion, Habitual↗
PubMed2005

Preimplantation genetic diagnosis for aneuploidy screening in women older than 37 years.

OBJECTIVE: To provide background information about the average aneuploidy and implantation rates of older patients after IVF with preimplantation genetic diagnosis for aneuploidy screening (PGD-AS) when the patients are subdivided into age categories; and to compare pregnancy outcome data after PGD-AS in this group of patients with a similar control group. DESIGN: Retrospective clinical study. SETTING: Patients in an academic reproductive medicine unit. PATIENT(S): All patients 37 years or older who had PGD-AS between October 1999 and December 2003 and all pregnant patients 37 years or older who had IVF/intracytoplasmic sperm injection without PGD-AS during the same period of time. INTERVENTION(S): IVF with PGD-AS. MAIN OUTCOME MEASURE(S): Aneuploidy rate, miscarriage rate, live birth rate, implantation rate, multiple pregnancy rate, and prenatal testing. RESULT(S): Three hundred ninety-four PGD-AS cycles of patients between 37 and 46 years of age were analyzed. The aneuploidy rate gradually increased with age. The implantation rate remained similar over all age groups. There was a trend to a lower miscarriage and multiple pregnancy rate in the PGD-AS group and a higher delivery/live birth rate. There were five elective terminations of pregnancy after prenatal testing and three late miscarriages due to prenatal testing in the control group. CONCLUSION(S): Preimplantation genetic diagnosis for aneuploidy screening can give valuable information to older patients concerning the reason why their IVF cycles are unsuccessful and whether it is worthwhile to continue IVF treatment, and it can help patients to avoid the emotional trauma that can occur after prenatal testing during the second trimester of pregnancy.

Adult↗
PubMed2004

Comparison of blastocyst transfer with or without preimplantation genetic diagnosis for aneuploidy screening in couples with advanced maternal age: a prospective randomized controlled trial.

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.

Adult↗
PubMedDate not supplied

Klinefelter syndrome: expanding the phenotype and identifying new research directions.

PURPOSE: The purpose of this study is to summarize new data on etiology and clinical features of Klinefelter syndrome in order to derive research priorities. METHODS: This study was conducted using critical reviews of selective topics, emphasizing less well-recognized clinical findings. RESULTS AND CONCLUSIONS: The phenotype of the prototypic 47,XXY case is well recognized: seminiferous tubule dysgenesis and androgen deficiency. Less well appreciated is the varied expressivity of 47,XXY Klinefelter syndrome, in particular neurological/cognitive perturbations like language and behavioral problems. Effective therapies are available. Reproductive technologies allow 47,XXY men to sire offspring through intracytoplasmic sperm injection (ICSI); however, genetic counseling is complex and success is low. Behavioral and expressive language difficulties are amenable to treatment by androgen therapy and psychological help. Early treatment may be imperative for optimal outcome.

Biomedical Research↗