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Fetal Chromosomal Abnormalities (fetal + chromosomal_abnormality)
Selected AbstractsAn examination of different fetal specific antibodies and magnetic activated cell sorting for the enrichment of fetal erythroblasts from maternal bloodCONGENITAL ANOMALIES, Issue 3 2002Xiao Xi Zhao ABSTRACT, The aim of the present study was to compare the rates of fetal cells obtained after separation from maternal blood by magnetic activated cell sorting (MACS) using different fetal specific antibodies, and to evaluate the potential role of this method in the prenatal diagnosis of fetal trisomies. Peripheral blood samples were obtained from 42 women carrying chromosomally normal fetuses and from 4 women with aneuploid fetuses (2 cases of 47,XX,+18 and 2 of 47,XY,+21) at 9,20 weeks of gestation. After fetal cells were enriched by MACS with three different monoclonal antibodies (GPA, CD71, CD14), fluorescence in situ hybridization (FISH) with chromosome X, and Y-specific probes was performed to detect the rates of fetal cells in the samples sorted. FISH with chromosome 13-, 18-, and 21-specific probes was carried out to compare proportions of cells with three-signal nuclei in chromosomally normal and abnormal groups. In male infants, X-and Y-positive cells were detected in 80%, 73.3%, and 66.6% of samples after the separation by antibodies CD14, GPA, and CD71, respectively. The percentage of nuclei with three signals was increased in pregnancies with trisomy, ranging between 2% and 5.18%. Pregnancies with normal fetuses showed 0 to 3.7% of nuclei with three signals. The data demonstrate that fetal cell detection varies depending on the antibodies used for cell sorting. This study provides further evidence on the feasibility of screening for fetal chromosomal abnormalities by enriching maternal blood for fetal cells and using FISH. [source] Noninvasive prenatal diagnosis of aneuploidy using cell-free nucleic acids in maternal blood: promises and unanswered questionsPRENATAL DIAGNOSIS, Issue 1 2008William M. Puszyk Abstract The discovery of cell-free fetal (cff) DNA and RNA in the maternal circulation has driven developments in noninvasive prenatal diagnosis (NIPD) for the past decade. Detection of paternally derived alleles in cff DNA is becoming well established. Now much interest is focussing on NIPD of fetal chromosomal abnormalities, such as trisomy 21, which is a considerable challenge because this demands accurate quantitative measurements of the amounts of specific cff DNA or cff RNA sequences in maternal blood samples. Emerging strategies for distinguishing and quantifying the fetal nucleic acids in the maternal circulation promise continued development of the field, and pose a number of unanswered questions. Copyright © 2007 John Wiley & Sons, Ltd. [source] The utility assessment of Chinese pregnant women towards the birth of a baby with Down syndrome compared to a procedure-related miscarriagePRENATAL DIAGNOSIS, Issue 9 2006Yiu Man Chan Abstract Objective This study was performed to investigate the preferences of Chinese pregnant women for Down syndrome-affected birth compared to invasive test-related miscarriage, using the standard gamble approach, and to investigate whether there is a difference in Utility Score between general obstetric patients and those who request prenatal screening. Methods An interviewer-administered survey was conducted on 67 women who presented to the General Obstetric Clinic for booking visits and 69 women who presented to the first-trimester Combined Screening Clinic for fetal Down syndrome in a University Obstetric Unit. Preferences for Down syndrome-affected birth compared to invasive test-related miscarriage were assessed using the standard gamble approach. The differences in Utility Scores for the two outcomes and difference in scores between the two study groups were compared. Results There was no significant difference in any of the Utility Scores studied between the two study groups. Therefore the summary statistics were performed using the whole study population. The median Utility Score for a Down syndrome-birth was 0.20 (IQR: 0.10,0.40), which was significantly lower than that of 0.55 (IQR: 0.40,0.80) for a procedure-related miscarriage (p < 0.001). Also, the Utility Scores were neither found to be associated with any particular patient demographic characteristics nor their perception of the functional disability of individuals with Down syndrome. Conclusion The Chinese pregnant women in Hong Kong consider a Down syndrome-affected birth as a much worse health state and life event than a miscarriage. Whether or not to have a screening test appeared to be a result of accessibility and affordability rather than fundamental differences in attitude towards Down syndrome. The findings of the study provide important information on how prenatal screening and diagnosis of fetal chromosomal abnormalities should be offered. Copyright © 2006 John Wiley & Sons, Ltd. [source] Maternal serum leptin concentration during the second trimester of pregnancy: association with fetal chromosomal abnormalitiesPRENATAL DIAGNOSIS, Issue 3 2002Demetrios Rizos Abstract Recent studies suggest that leptin, the product of the obese gene, is produced by the placenta during pregnancy. The present study addressed the question whether second trimester maternal serum leptin could be altered by fetal Down syndrome or Edwards syndrome. Maternal serum leptin concentrations were measured in 18 pregnancies complicated with Down syndrome, six pregnancies complicated with Edwards syndrome and 183 uncomplicated pregnancies during the second trimester of pregnancy. The present results demonstrate that leptin concentrations in uncomplicated pregnancies slightly decrease from the 16th week of pregnancy, reaching a minimum of 18.8,ng/ml around the 20th week, and then rapidly increase to 28.2,ng/ml by the 24th week. Leptin correlation with maternal body weight decreases from r=0.695 at 16,17 week of gestation to r=0.544 at >22 weeks of gestation. There was no significant difference between the mean MoMs of Down syndrome- (0.926) or Edwards syndrome- (0.960) affected pregnancies and normal pregnancies (1.002). A weak correlation (r=0.18, p<0.02) was observed between corrected leptin MoMs and human chorionic gonadotrophin (hCG) MoMs in normal pregnancies. It is assumed that around the 20th week of pregnancy placental leptin production is activated or at least is accelerated and it is added to the amount of leptin produced by maternal adipose tissue. Fetal Down syndrome or Edwards syndrome does not seem to alter maternal leptin concentration and therefore leptin cannot be used as a marker for these chromosomal abnormalities in the early second trimester of pregnancy. Copyright © 2002 John Wiley & Sons, Ltd. [source] Total alpha-fetoprotein and Lens culinaris agglutinin-reactive alpha-fetoprotein in fetal chromosomal abnormalitiesBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 11 2001Ritsu Yamamoto Objective To examine the differences in multiples of the median (MoM) of total alpha-fetoprotein, and the proportion of Lens culinaris agglutinin reactive alpha-fetoprotein (% alpha-fetoprotein-L2+L3) in the maternal serum and amniotic fluid of pregnant women whose fetuses were diagnosed with autosomal or sex chromosomal abnormalities. Design Prospective consecutive series. Setting University hospital. Sample Maternal sera and amniotic fluids from 46 pregnant women with trisomy 21 fetuses, 10 pregnant women with trisomy 18 fetuses, one pregnant woman with a trisomy 13 fetus, six pregnant women with fetal sex chromosomal abnormalities, and 100 pregnant women for whom the fetal karyotype was diagnosed as normal following a genetic amniocentesis. Results The proportion of alpha-fetoprotein-L2+L3 in maternal serum for trisomy 21 (40.3%, P<0.0001) and trisomy 18 (39.8%, P<0.05) showed a significantly higher value compared with normal (32.6%). The proportion of alpha-fetoprotein-L2+L3 in amniotic fluid was significantly higher (P<0.0001) for trisomy 21 (46.6%) than for a normal karyotype (41.5%). Only for the trisomy 21 group was there a strong correlation in the % alpha-fetoprotein-L2+L3 between maternal serum and amniotic fluid (r=0.840, P<0.0001). For all groups, there was no correlation between alpha-fetoprotein MoM and % alpha-fetoprotein-L2+L3 in maternal serum and amniotic fluid. Conclusion The proportion of alpha-fetoprotein-L2+L3 in maternal serum is an appropriate choice for a trisomy 21 biochemical marker, and it is possible that combining alpha-fetoprotein-L2+L3 analysis with assays of alpha-fetoprotein in maternal serum could further improve the sensitivity and specificity of multiple marker screening. [source] Awareness and attitude toward prenatal diagnosis of chromosomal abnormalities in patients with no access to legal termination of pregnancyPRENATAL DIAGNOSIS, Issue 10 2006E. Gadow Abstract Objective To analyze variables affecting couples' decision making about prenatal cytogenetic diagnosis in patients with no access to legal termination of pregnancy (TOP). Methods Patients undergoing invasive prenatal diagnosis were anonymously surveyed after counseling and before the procedure. The questionnaire enquired about sociodemographic features, medical history, knowledge of and attitudes toward genetic testing and TOP. Results Two genetic units distributed 372 questionnaires. Mean maternal age was 36 ± 4 years. Access to prenatal genetic counseling was mainly patient's own initiative, or ,self-referral'. Most self-referred patients (87%) considered that ,receiving accurate information' was the main issue. Eighty-one per cent of all couples knew that TOP because of fetal anomalies was not legal. In case of a serious anomaly, 68.2% of patients would contemplate TOP, in spite of the risk of being exposed to an unsafe abortion. Conclusions In many countries, prenatal genetic testing is offered, but TOP is not available. In the present study, although most of the couples who decided to undergo prenatal genetic testing were aware of this, they still chose to perform prenatal diagnosis. The main reason given was to obtain reliable information about fetal condition. Finally, if a fetal chromosomal abnormality were detected, most of them would consider TOP. Copyright © 2006 John Wiley & Sons, Ltd. [source] | ||||||||||