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Ribas Seix Isabel - One of the best experts on this subject based on the ideXlab platform.

  • Anomalies cromosòmiques en avortaments espontanis de primer trimestre
    2005
    Co-Authors: Ribas Seix Isabel
    Abstract:

    Consultable des del TDXTítol obtingut de la portada digitalitzadaEs defineix com a avortament espontani la interrupció d'una gestació abans de la setmana 22, i a pesar de que s'han descrit diversos factors etiològics, es desconeix la causa en la majoria de casos. La presència d'una anomalia cromosòmica en l'embrió és, presumiblement, la causa per la que es produeix l'avortament en el 70% dels casos corresponents al primer trimestre de la gestació, si bé aquest primer període és el menys estudiat degut a les dificultats que presenta l'anàlisi de l'embrió. En aquest treball s'ha tractat la gestació interrumpuda espontàniament exactament igual que a la gestació evolutiva a la que es vol realitzar un diagnòstic prenatal cromosòmic durant el primer trimestre de la gestació: es realitza una biòpsia de corion sota control ecogràfic i, un cop triades les vellositats coriòniques, s'apliquen en paral·lel dues tècniques citogenètiques, com són el mètode semi-directe i el cultiu llarg. De les 142 mostres rebudes, s'obtingué un resultat citogenètic en 130 (91.5%), que corresponien a 131 embrions perquè una de les gestacions biopsiades resultà ser doble. La incidència d'anomalies cromosòmiques ha estat del 67.2%. Les trisomies autosòmiques representen un 70.5% del total d'anomalies cromosòmiques detectades, i les més freqüents van ser les trisomies pels cromosomes 16, 22 i 15. La monosomia X es trobà en un 11.4% i les anomalies estructurals en un 9.1% (herències desequilibrades en la majoria dels casos), i el 9.1% de poliploidies corresponien a 6 triploidies i 2 tetraploidies. Finalment, s'ha descrit un cas de monosomia pel cromosoma 21. (Taula 1). Taula 1.- Tipus d'anomalies cromosòmiques presents: TOTAL: 31 embrions cariotip normal: 43 (32.8%) analizats cariotip patològic: 88 (67.2%) Trisomies: 62 (70.5%) trisomia 16: 20.7% trisomia 22: 17.2% trisomia 15: 15.5% trisomia 13: 8.6% Monosomia X: 10 (11.4%) Anomalies estructurals: 8 (9.1%) Poliploidies: 8 (9.1%) triploidia: 6 (6.8%) tetraploidia: 2 (2.3%) Monosomia 21: 1 (1.1%) Les principals conclusions que es desprenen d'aquest treball són que la presència d'anomalies cromosòmiques en els avortaments espontanis del primer trimestre de la gestació és un fenòmen molt freqüent, i que és necessari analitzar citogenèticament aquests embrions per tal de trobar la causa de l'avortament i poder realitzar un correcte assessorament reproductiu davant de futures gestacions. El millor mètode ha resultat la realització d'una biòpsia de corion i l'aplicació del mètode semi-directe en paral·lel al cultiu llarg de vellositats coriòniques, seguint en tot moment el mateix protocol usat per al diagnòstic prenatal cromosòmic de gestacions evolutives.Chromosome abnormalities are the most frequent cause of spontaneous abortion, which is defined as the termination of pregnancy before the 22th week. More than 70% of early pregnancy losses (before the 12 week of pregnancy) have a chromosome defect. But, in spite of this, there are a very few cytogenetic studies of that period, because of the technical difficulties in finding embryo tissue to culture. Early pregnancy losses have been studied in this investigation as in on-going first-trimester pregnancies: e.g. a Chorion Villus Sampling was made under ultrasonographic control. The karyoype was analyzed by semi-direct analysis and/or long term culture. Cytogenetic results were obtained from 130 of 142 samples (91.5%), and 131 embryos were analized (one of the samples came from a twin pregnancy). The rate of chromosome abnormalities was 67.2%. Trisomy was present in 70.5% of the abnormal cases, and the most frequent chromosomes involved in trisomy were 16, 22 and 15. Monosomy X was found in 11.4% of the samples and structural anomalies in 9.1% (specially unbalanced familial abnormalities). Poliploidy was found in 9.1% of abnormal cases, corresponding to 6 triploidies and 2 tetraploidies. Finally, one case of monosomy 21 was found. (Table 1). Table 1.- Chromosome abnormalities TOTAL: 131 embryos normal karyotype: 43 (32.8%) abnormal karyotype: 88 (67.2%) Trisomy: 62 (70.5%) trisomy 16: 20.7% trisomy 22: 17.2% trisomy 15: 15.5% trisomy 13: 8.6% Monosomy X: 10 (11.4%) Structural abnormalities: 8 (9.1%) Poliploidy: 8 (9.1%) triploidy: 6 (6.8%) tetraploidy: 2 (2.3%) Monosomy 21: 1 (1.1%) In conclusion, chromosome abnormalities had proven to be a very important cause of early pregnancy loss. Therefore, it is advisable to analyse the karyotype of all spontaneous abortions, in order to clarify its cause and to assess the reproductive significance for future pregnancies. Chorionic Villus Sampling is a good method to obtain embryonic material for cytogenetc analysis in early pregnancy losses

  • Anomalies cromosòmiques en avortaments espontanis de primer trimestre
    2002
    Co-Authors: Ribas Seix Isabel
    Abstract:

    Es defineix com a avortament espontani la interrupció d'una gestació abans de la setmana 22, i a pesar de que s'han descrit diversos factors etiològics, es desconeix la causa en la majoria de casos. La presència d'una anomalia cromosòmica en l'embrió és, presumiblement, la causa per la que es produeix l'avortament en el 70% dels casos corresponents al primer trimestre de la gestació, si bé aquest primer període és el menys estudiat degut a les dificultats que presenta l'anàlisi de l'embrió.En aquest treball s'ha tractat la gestació interrumpuda espontàniament exactament igual que a la gestació evolutiva a la que es vol realitzar un diagnòstic prenatal cromosòmic durant el primer trimestre de la gestació: es realitza una biòpsia de corion sota control ecogràfic i, un cop triades les vellositats coriòniques, s'apliquen en paral.lel dues tècniques citogenètiques, com són el mètode semi-directe i el cultiu llarg. De les 142 mostres rebudes, s'obtingué un resultat citogenètic en 130 (91.5%), que corresponien a 131 embrions perquè una de les gestacions biopsiades resultà ser doble.La incidència d'anomalies cromosòmiques ha estat del 67.2%. Les trisomies autosòmiques representen un 70.5% del total d'anomalies cromosòmiques detectades, i les més freqüents van ser les trisomies pels cromosomes 16, 22 i 15. La monosomia X es trobà en un 11.4% i les anomalies estructurals en un 9.1% (herències desequilibrades en la majoria dels casos), i el 9.1% de poliploidies corresponien a 6 triploidies i 2 tetraploidies. Finalment, s'ha descrit un cas de monosomia pel cromosoma 21. (Taula 1).Taula 1.- Tipus d'anomalies cromosòmiques presents:TOTAL: 31 embrions cariotip normal: 43 (32.8%) analizats cariotip patològic: 88 (67.2%) Trisomies: 62 (70.5%) trisomia 16: 20.7% trisomia 22: 17.2% trisomia 15: 15.5% trisomia 13: 8.6% Monosomia X: 10 (11.4%) Anomalies estructurals: 8 (9.1%) Poliploidies: 8 (9.1%) triploidia: 6 (6.8%) tetraploidia: 2 (2.3%) Monosomia 21: 1 (1.1%) Les principals conclusions que es desprenen d'aquest treball són que la presència d'anomalies cromosòmiques en els avortaments espontanis del primer trimestre de la gestació és un fenòmen molt freqüent, i que és necessari analitzar citogenèticament aquests embrions per tal de trobar la causa de l'avortament i poder realitzar un correcte assessorament reproductiu davant de futures gestacions. El millor mètode ha resultat la realització d'una biòpsia de corion i l'aplicació del mètode semi-directe en paral.lel al cultiu llarg de vellositats coriòniques, seguint en tot moment el mateix protocol usat per al diagnòstic prenatal cromosòmic de gestacions evolutives.Chromosome abnormalities are the most frequent cause of spontaneous abortion, which is defined as the termination of pregnancy before the 22th week. More than 70% of early pregnancy losses (before the 12 week of pregnancy) have a chromosome defect. But, in spite of this, there are a very few cytogenetic studies of that period, because of the technical difficulties in finding embryo tissue to culture.Early pregnancy losses have been studied in this investigation as in on-going first-trimester pregnancies: e.g. a Chorion Villus Sampling was made under ultrasonographic control. The karyoype was analyzed by semi-direct analysis and/or long term culture.Cytogenetic results were obtained from 130 of 142 samples (91.5%), and 131 embryos were analized (one of the samples came from a twin pregnancy).The rate of chromosome abnormalities was 67.2%. Trisomy was present in 70.5% of the abnormal cases, and the most frequent chromosomes involved in trisomy were 16, 22 and 15. Monosomy X was found in 11.4% of the samples and structural anomalies in 9.1% (specially unbalanced familial abnormalities). Poliploidy was found in 9.1% of abnormal cases, corresponding to 6 triploidies and 2 tetraploidies. Finally, one case of monosomy 21 was found. (Table 1).Table 1.- Chromosome abnormalities TOTAL: 131 embryos normal karyotype: 43 (32.8%) abnormal karyotype: 88 (67.2%) Trisomy: 62 (70.5%) trisomy 16: 20.7% trisomy 22: 17.2% trisomy 15: 15.5% trisomy 13: 8.6% Monosomy X: 10 (11.4%) Structural abnormalities: 8 (9.1%) Poliploidy: 8 (9.1%) triploidy: 6 (6.8%) tetraploidy: 2 (2.3%) Monosomy 21: 1 (1.1%) In conclusion, chromosome abnormalities had proven to be a very important cause of early pregnancy loss. Therefore, it is advisable to analyse the karyotype of all spontaneous abortions, in order to clarify its cause and to assess the reproductive significance for future pregnancies. Chorionic Villus Sampling is a good method to obtain embryonic material for cytogenetc analysis in early pregnancy losses

Helen V Firth - One of the best experts on this subject based on the ideXlab platform.

  • Chorion Villus Sampling and limb deficiency cause or coincidence
    1997
    Co-Authors: Helen V Firth
    Abstract:

    Chorion Villus Sampling (CVS) is a widely used technique in first trimester prenatal diagnosis. In the early 1990s, two clusters of babies with limb defects following CVS were reported, raising the possibility of a causal association between early CVS and transverse limb deficiency. The evidence for this association is reviewed and shows a diminishing risk for transverse limb deficiency with advancing gestation. The risk of limb deficiency extends through the period of limb morphogenesis and slightly beyond; falling from levels 10-20-fold above background at nine weeks and below, to levels approaching (or only a few-fold above) background at 11 weeks and beyond.

  • severe limb abnormalities after Chorion Villus Sampling at 56 66 days gestation
    1991
    Co-Authors: Helen V Firth, Patriciaa Boyd, R H Lindenbaum, Susan M Huson, P Chamberlain, I Z Mackenzie
    Abstract:

    Abstract Among 289 pregnancies in which Chorion Villus Sampling (CVS) was carried out at 56-66 days' gestation, 5 babies with severe limb abnormalities were subsequently identified. 4 had oromandibularlimb hypogenesis syndromes, and the other had a terminal transverse limb reduction defect. This high incidence raises the possibility that CVS was an aetiological factor for these developmental anomalies.

Los F.j. - One of the best experts on this subject based on the ideXlab platform.

  • Fetal ductus venosus flow velocity waveforms and maternal serum AFP before and after first-trimester transabdominal Chorionic Villus Sampling
    1995
    Co-Authors: Brezinka Christoph, Hagenaars A., Wladimiroff Juriy, Los F.j.
    Abstract:

    textabstractDoppler flow velocity waveform recording in the fetal ductus venosus and umbilical artery as well as maternal blood Sampling for serum alpha-fetoprotein (MSAFP) was performed before and after transabdominal Chorion Villus Sampling (TACVS) in 36 women of advanced maternal age (≥ 36 years). Gestational age ranged between 11 and 13 weeks. No chromosomal anomaly was detected. No statistically significant difference was observed in ductus venosus velocity parameters or in the umbilical artery pulsatility index (PI) before and after CVS in 35 women with a normal pregnancy outcome. One case resulted in fetal loss. Post-CVS median MSAFP levels at 12 weeks (25 kIU/1) and 13 weeks (35 kIU/1) were significantly higher than pre-CVS levels. In three cases, post-CVS MSAFP levels were higher than 600 kIU/1, correlating with feto-maternal transfusions of approximately 1.0–1.4 ml, i.e., of around 40 per cent of feto-placental blood volume. One of these cases displayed absence of fetal peripheral blood flow velocities and fetal bradycardia following TACVS, resulting in fetal loss 1 week later. The remaining two cases had a normal pregnancy outcome, but showed a more than 50 per cent reduction in ductus venosus velocity after TACVS, whereas umbilical artery PI remained unchanged. However, similar velocity changes were associated with only small feto-maternal transfusions. Umbilical artery PI values remained unchanged

  • Fetal ductus venosus flow velocity waveforms and maternal serum AFP before and after first-trimester transabdominal Chorionic Villus Sampling
    1995
    Co-Authors: Brezinka C.a., Hagenaars A.m., Wladimiroff J.w., Los F.j.
    Abstract:

    Doppler flow velocity waveform recording in the fetal ductus venosus and umbilical artery as well as maternal blood Sampling for serum alpha-fetoprotein (MSAFP) was performed before and after transabdominal Chorion Villus Sampling (TACVS) in 36 women of advanced maternal age (≥ 36 years). Gestational age ranged between 11 and 13 weeks. No chromosomal anomaly was detected. No statistically significant difference was observed in ductus venosus velocity parameters or in the umbilical artery pulsatility index (PI) before and after CVS in 35 women with a normal pregnancy outcome. One case resulted in fetal loss. Post-CVS median MSAFP levels at 12 weeks (25 kIU/1) and 13 weeks (35 kIU/1) were significantly higher than pre-CVS levels. In three cases, post-CVS MSAFP levels were higher than 600 kIU/1, correlating with feto-maternal transfusions of approximately 1.0–1.4 ml, i.e., of around 40 per cent of feto-placental blood volume. One of these cases displayed absence of fetal peripheral blood flow velocities and fetal bradycardia following TACVS, resulting in fetal loss 1 week later. The remaining two cases had a normal pregnancy outcome, but showed a more than 50 per cent reduction in ductus venosus velocity after TACVS, whereas umbilical artery PI remained unchanged. However, similar velocity changes were associated with only small feto-maternal transfusions. Umbilical artery PI values remained unchanged

Zarko Alfirevic - One of the best experts on this subject based on the ideXlab platform.

  • early amniocentesis versus transabdominal Chorion Villus Sampling for prenatal diagnosis
    1999
    Co-Authors: Zarko Alfirevic
    Abstract:

    Reason for withdrawal from publication This review has been withdrawn as it has been incorporated into the currently published review entitled 'Amniocentesis and Chorionic Villus Sampling for prenatal diagnosis'. To view the published versions of this article, please click the 'Other versions' tab.

  • Chorion Villus Sampling versus amniocentesis for prenatal diagnosis
    1996
    Co-Authors: Zarko Alfirevic, C M Gosden, James P Neilson
    Abstract:

    Background Amniocentesis test results are usually available only after 18 weeks gestation. Chorion Villus Sampling (CVS) may be performed transabdominally or transvaginally, usually between 10 and 12 weeks gestation. Objectives The objective of this review was to assess the safety and accuracy of Chorion Villus Sampling compared to amniocentesis. Search strategy We searched the Cochrane Pregnancy and Childbirth Group trials register. Selection criteria Randomised trials comparing first trimester Chorion Villus Sampling and second trimester amniocentesis. Data collection and analysis Trial quality was assessed. Main results Three studies involving over 9000 women were included. The trials were generally of good quality. Compared to amniocentesis, Chorion Villus Sampling was associated with more Sampling and technical failures, and more false positive and false negative results. Pregnancy loss was more common after Chorion Villus Sampling (odds ratio 1.33, 95% confidence interval 1.17 to 1.52). There is a suggestion (though not statistically significant) of an increase in stillbirths and neonatal deaths following Chorion Villus Sampling. Maternal complications were uncommon. Reviewer's conclusions The increase in miscarriages after Chorion Villus Sampling compared to amniocentesis appear to be procedure related. Second trimester amniocentesis appears to be safer than Chorion Villus Sampling. The benefits of earlier diagnosis with Chorion Villus Sampling must be set against the greater risk of pregnancy loss.

Jane Halliday - One of the best experts on this subject based on the ideXlab platform.

  • limb deficiencies Chorion Villus Sampling and advanced maternal age
    1993
    Co-Authors: Jane Halliday, Leslie J Sheffield, Judith Lumley, Paul A L Lancaster
    Abstract:

    Record linkage between a prenatal diagnosis register and a congenital malformation register in the state of Victoria, Australia, has enabled further evaluation of the suggested association between limb deficiencies and early Chorion Villus Sampling (CVS). We found 3 anomalies in this category after later CVS (i.e., 9 weeks and beyond), but our data suggest that advanced maternal age may be a risk factor for both terminal and all limb deficiencies. The data from Victoria are tabulated with data obtained from other registers. Different birth prevalence figures are obtained by different registers, therefore limiting comparisons between registers. © 1993 Wiley-Liss, Inc.

  • importance of complete follow up of spontaneous fetal loss after amniocentesis and Chorion Villus Sampling
    1992
    Co-Authors: Jane Halliday, Leslie J Sheffield, Judith Lumley, Hugh P Robinson, Peter Renou, John B Carlin
    Abstract:

    Abstract Women who are the most difficult to trace after amniocentesis or Chorion Villus Sampling are often those who have had an adverse pregnancy outcome. To calculate total fetal loss figures for use in prenatal counselling we have followed in a multicentre study 100% of women who had undergone these procedures. Early spontaneous loss (within three weeks of the procedure) and total spontaneous loss were much lower after amniocentesis (0·2% and 1·3%, respectively) than after Chorion Villus Sampling (1·2% and 2·9%). Four spontaneous fetal losses among the 20 pregnancies that were the most difficult to follow-up increased the loss rate by 0·5% for Chorion Villus Sampling. Risk of early fetal loss after Chorion Villus Sampling was related to experience of the operator (relative risk [RR] 4·3, p=0·003), and total fetal loss was lower in pregnancies tested at 10 weeks' or more gestational age compared with those tested before 10 weeks' (RR 0·4, p=0·01). A table showing the frequency of each of the seven possible outcomes after amniocentesis and Chorion Villus Sampling is useful in counselling those considering one or other test.