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Objective:To analyze the genetic etiology and prognosis in fetuses with increased nuchal translucency (NT) in order to assist in the clinical prenatal genetic counseling and diagnosis.Methods:This study retrospectively enrolled 1 658 cases of singleton pregnancy (<35 years old) receiving invasive prenatal diagnosis, including karyotype analysis and/or chromosome microarray analysis or copy number variation (CNV) sequencing, due to NT value ≥2.5 mm in the first trimester in Henan Provincial People's Hospital from August 2014 to December 2021. They were divided into different groups according to the thickness of NT (≥2.5-<3.0, ≥3.0-<3.5, ≥3.5-<4.5, ≥4.5-<5.5, ≥5.5-<6.5 and ≥6.5 mm groups) and abnormal ultrasound findings (isolated increased NT group, increased NT complicated by soft markers/non-severe structural abnormality group and increased NT complicated by severe structural abnormality group). The results of invasive prenatal diagnosis and pregnancy outcomes were compared between different groups using Chi-square test and trend Chi-square test. Results:The detection rates of numerical abnormalities of chromosomes were 15.8% (262/1 658) and 17.6% (252/1 431) when the NT thickness cut-off value were 2.5 mm or 3.0 mm, respectively. Overall, the detection rate of numerical abnormalities of chromosomes increased with thickness of NT ( χ2trend=180.75, P<0.001), ranging from 6.6% (44/671) in the NT≥2.5-<3.5 mm group to 45.6% (113/248) in the NT≥5.5 mm group. The incidence of pathogenic/likely pathogenic CNV(P/LP CNV) did not increased with NT thickness ( χ2trend=3.26, P=0.071), and the highest detection rate was observed in the NT≥4.5-<5.5 mm group (9.0%, 19/211). The detection rate of numerical abnormalities of chromosomes plus P/LP CNV in the isolated NT≥2.5-<3.0 mm group and NT≥3.0-<3.5 mm group were 5.3% (10/188) and 9.6% (36/375), respectively, however, the difference was not statistically significant ( χ2=3.06, P=0.080). The detection rates of numerical abnormalities of chromosomes plus P/LP CNV in the isolated NT≥3.5-<4.5 mm group and NT≥2.5-<3.0 mm complicated by soft markers/ non-severe structural abnormality group were 12.7% (52/410) and 24.1% (7/29), respectively, and the risk were 2.6 times (95% CI: 1.3-5.2) and 5.7 times (95% CI: 2.0-16.4) of the isolated NT≥2.5-<3.0 mm group, respectively. The pregnancy termination rate increased with the NT thickness ( χ2trend=304.42, P<0.001), ranging from 10.8% (23/212) in the NT≥2.5-<3.0 mm group to 90.7% (117/129) in the NT≥6.5 mm group. After exclusion of the pregnancies terminated due to numerical abnormalities of chromosomes and P/LP CNV, 87.6% (862/984) of the fetus with increased NT were born alive. Conclusions:The detection rate of numerical abnormalities of chromosomes increases with the thickness of NT. Invasive prenatal diagnosis is required for non-advance aged singleton pregnant women when fetuses present with isolated NT≥2.5 mm with or without soft markers/structural abnormalities.
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Objective:To analyze the genetic etiology of 487 fetuses with increased nuchal translucency (NT) using copy number variant sequencing (CNV-seq) and explore the relationship between increased NT and chromosomal abnormality.Methods:A retrospective study was performed on 487 fetuses with increased NT who received CNV-seq in the First Affiliated Hospital of Zhengzhou University from January 2018 to December 2020. These fetuses either had NT of ≥3.0-<3.5 mm (Group A, n=129) or ≥3.5 mm (Group B, n=358), the distribution and incidence of chromosomal abnormalities in the two sets of fetuses were analyzed using Chi square test or Fisher's exact test. Results:Fetuses with abnormal chromosomes accounted for 25.9%(126/487) of cases, including 107 with chromosome aneuploidy (22.0%) and 19 with pathogenic or likely pathogenic copy number variation (CNV, 3.9%). The detection rate of fetal aneuploidy in Group B was higher than that in Group A [14.0% (18/129) vs 24.9% (89/358), χ2=6.58, P=0.010]. However, no significant difference was observed regarding the detection rate of pathogenic or likely pathogenic CNV between the two groups ( χ2=0.30, P=0.584). Conclusions:The risk of fetal chromosome aneuploidy increased with NT thickness, but not with pathogenic or likely pathogenic CNV, which needed further verification due to the small sample size. CNV-seq is an option to detect the conventional detection methods for the genetic etiology of NT thickening fetuses.
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Objective:To compare the prenatal diagnosis and pregnancy outcome of increased nuchal translucency (NT) with or without nuchal cystic hygroma (CH) in fetuses with first-trimester NT ≥5 mm.Methods:Data from 131 fetuses with NT ≥5 mm who received invasive prenatal diagnosis at Guangzhou Women and Children's Medical Center from July 2017 to December 2020 were retrospectively collected and analyzed. Those with a septum in the cyst were grouped as NT with CH group ( n=57), and those without as increased NT without CH group ( n=74). Genetic test results, incidence of structural malformations, survival rate after birth were compared using Chi-square test or Fisher's exact test and non-parametric test. Results:There was no significant difference in the incidence of fetal genetic abnormalities[67.6%(50/74) vs 61.4%(35/57), χ 2=0.54, P=0.464], ultrasonic structural malformations [21.6%(16/74) vs 33.3%(19/57), χ 2=2.26, P=0.133], or in the survival rate (12/14 vs 3/8, P=0.053) between increased NT without CH group and NT with CH group. Conclusions:For increased NT with or without CH, although the two groups had different spectrum of disease, they had a high incidence of chromosomal abnormalities and structural malformations, and both groups had a certain healthy survival rate after birth.
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Objective@#To explore the relationship between fetal nuchal translucency (NT) in the first trimester and pregnancy outcome.@*Methods@#A prospective cohort study was conducted in Nanjjing Drum Tower Hospital from December 2015 to December 2018, 4 958 singleton pregnant women were enrolled to screen fetal ultrasound structure and serology in the first trimester, ultrasound in the second trimester and neonatus physical examination 28 days after birth. According to the results of NT, 167 cases of fetus with increased NT (≥3.0 mm) and 4 791 cases of normal NT were divided, moreover, 86 cases with isolate increased NT and 81 cases of increased NT combined with structural abnormality. The prognosis of fetuses with different NT thickness was analyzed, and the pregnancy outcome of fetuses with isolate increased NT or combined with structural abnormality were analyzed. In the first trimester, if the fetal structure was abnormal or the serological screening result was high risk, the chromosomal microarray analysis (CMA) would be performed by chorionic villus sampling to determine the prenatal diagnosis.@*Results@#(1) The pregnancy outcome for fetus of normal NT: there were 4 791 cases with normal NT. Totally, 4 726 cases with normal NT and no structural abnormalities were screened out in the firsttrimester. In this group, 5 cases of aneuploidies were diagnosed based on high risk of maternal serum biomarkers and 83 cases of structural abnormalities were screened out in the subsequent ultrasound scan and the neonatal examination. Another 65 cases with normal NT present complicated with structural anomalies were screened out in the first trimester and 4 cases were diagnosed as aneuploidies. (2) The pregnancy outcome for fetus of isolate increased NT: 66 (76.7%, 66/86) cases of isolated increased NT were performed CMA, 3 cases were diagnosed as trisomy 21 and terminated pregnancy. Another 4 cases were terminated pregnancy privately without cytogenetic diagnosis. No further anomalies were found in 79 cases till 6 to 21 months postnatally. (3) The pregnancy outcome for fetus of increased NT with structural anomalies: increased NT present with structural anomalies were screened out by detailed anomaly scan in the first trimester and 32 of them were confirmed as aneuploidies. In this group, 70 cases terminated pregnancy, 2 cases had spontaneous miscarriages and 9 cases had liveborns (1 newborn was found ventricular septal defect). (4) The pregnancy outcome for fetus of increased NT with or without structural anomalies: the percentage of aneuploidies in fetuses with isolated increased NT (3.5%, 3/86) was significantly lower than those with structural abnormalities (39.5%,32/81). The healthy survival rate in fetuses with isolated increased NT (91.9%,79/86) was significantly higher than those with structural abnormalities (9.9%, 8/81).@*Conclusions@#A detailed first-trimester anomaly scan could improve prenatal screening efficiency of birth defects. Compared to the fetuses with increased NT combined with structural abnormalities, the healthy survival rate of fetuses with isolated increased NT based on detailed first-trimester anomaly scan is higher and the percentage of fetal aneuploidies is lower.
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We reported the prenatal molecular diagnosis and pregnant outcome of a fetus with increased nuchal translucency.The ultrasound findings of the gravida at 12+5 gestational weeks indicated that the fetal nuchal translucency thickness was 4.5 mm,and non-invasive prenatal testing suggested as low risk.Amniocentesis was performed at 18 gestational weeks.Fetal chromosomal karyotype was normal but chromosome microarray comparative genomic hybridization analysis identified a 1.878 Mb deletion on chromosome 2p15-16.1.No copy number variation was found in the parents.The microdeletion was also verified by multiplex ligation-dependent probe amplification.Literature reported that chromosome 2p 15-16.1 microdeletion syndrome was characterized by mental retardation,language developmental disorder,microcephaly and so on.This case we reported here was a de novo 2p 15-16.1 microdeletion which contained the critical region and genes of 2p 15-16.1 microdeletion syndrome and was inferred to be a pathogenetic mutation.The gravida chose to terminate the pregnancy after genetic consultation.
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Objective To investigate the diagnostic value of ultrasound scan at 16 to 18 gestational weeks in euploid fetuses with increased nuchal translucency (NT).Methods From January 2015 to June 2017,214 fetuses diagnosed with increased NT thickness (NT ≥ 3.0 mm) during early pregnancy in Guangzhou Panyu Central Hospital were enrolled.Fetal chromosome karyotype analysis was carried out prenatally.Those cases with normal karyotype underwent ultrasound scan at 16-18 and 20-24 gestational weeks and their outcomes were followed up via telephone.Descriptive statistics was used for statistical analysis.Results There were 198 out of the 214 cases undergoing chromosome karyotype analysis and among them,78 (39％) pregnancies were terminated due to chromosomal abnormalities.Out of the 107 cases with normal karyotype and successful followups,35％(37/107) had structural malformations.There were 19,11 and 6 cases of fetal structural malformations diagnosed at 11-13+6,16-18 and 20-24 weeks of gestational age,respectively,and the rest one was at 28 weeks.Structural deformities detected at 16-18 weeks included cleft lip and palate (n=2),cardiac malformations (n=2),spinal deformities (n=2),body deformities (n=2),diaphragmatic hernia (n=1),encephalocele (n=1) and left multicystic dysplastic kidney (n=1).About 91％ (70/77) of the fetuses with normal karyotype but without abnormal ultrasound findings at 16-18 weeks were free of structural malformations and achieved good pregnant outcomes.Conclusions Ultrasound screening at 16 to 18 weeks of pregnancy can be used to detect multiple structural malformations in fetuses with increased NT and normal karyotype,which may contribute to early detection of fetal structural malformations and help gravidas and their families make timely decisions.
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Objective@#To investigate the value of first-trimester ultrasound parameters in predicting complicated monochorionic diamniotic (MCDA) twins.@*Methods@#In this retrospective study, pregnant women diagnosed as MCDA twins by ultrasound in the First Affiliated Hospital of Sun Yat-sen University from January 2013 to January 2018 were recruited and divided into the following four groups: non-complicated MCDA twins group, twin-twin transfusion syndrome (TTTS) group, selective intrauterine growth restriction (sIUGR) group and twin anemia-polycythemia sequence (TAPS) group. Thickness of nuchal translucency (NT), crown-rump length (CRL), umbilical cord insertion (UCI) and ductus venosus (DV) flow at 11-14 weeks of gestation were recorded. The predictive value for complicated MCDA twins was analyzed using t-test, Chi-square (or Fisher's exact) test, multivariate logistic regression analysis and receiver operating characteristic (ROC) curve.@*Results@#(1) A total of 430 MCDA twin pregnancies were included in this study with 152 in the TTTS group, 142 in the sIUGR group, seven in the TAPS group and 129 in the normal MCDA twins group. No further analysis was performed on the TAPS group due to the small sample size. (2) NT discordance in twins of the TTTS group was significantly greater than that in the normal MCDA twins group[(21.5±16.0)% vs (14.6±13.5)%, t=-3.533, P<0.001]. The area under ROC curve (AUC) of TTTS predicted by NT discordance was 0.649. Stratified analysis showed that TTTS was best predicted when NT discordance was 20% with the sensitivity of 57.9% and specificity of 70.6%. (3) The sIUGR group had greater discordance in CRL and NT and higher UCI discordance than the normal MCDA twins group [NT: (27.8±21.3)% vs (14.6±13.5)%, t=-5.556, P<0.001; CRL: (8.6±6.9)% vs (5.4±4.4)%, t=-3.144, P=0.002; UCI: 47.9% (68/142) vs 13.9% (18/129), χ2=35.929, P<0.001]. The AUC of sIUGR was 0.675 predicted by NT discordance and 0.649 by CRL discordance. Stratified analysis showed that NT discordance of 20% and CRL discordance of 10% were the best prediction for sIUGR with the sensitivity of 53.1% and 34.7% and specificity of 72.1% and 83.8%, respectively. Multivariate logistic regression analysis suggested that UCI discordance was the risk factor for sIUGR (OR=7.165, 95%CI: 2.637-19.472).@*Conclusions@#MCDA twins with NT discordance greater than 20% during early pregnancy are at increased risk for TTTS. CRL discordance greater than 10%, NT discordance greater than 20% and abnormal UCI are risk factors for sIUGR.
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Objective To investigate the value of first-trimester ultrasound parameters in predicting complicated monochorionic diamniotic (MCDA) twins. Methods In this retrospective study, pregnant women diagnosed as MCDA twins by ultrasound in the First Affiliated Hospital of Sun Yat-sen University from January 2013 to January 2018 were recruited and divided into the following four groups: non-complicated MCDA twins group, twin-twin transfusion syndrome (TTTS) group, selective intrauterine growth restriction (sIUGR) group and twin anemia-polycythemia sequence (TAPS) group. Thickness of nuchal translucency (NT), crown-rump length (CRL), umbilical cord insertion (UCI) and ductus venosus (DV) flow at 11-14 weeks of gestation were recorded. The predictive value for complicated MCDA twins was analyzed using t-test, Chi-square (or Fisher's exact) test, multivariate logistic regression analysis and receiver operating characteristic (ROC) curve. Results (1) A total of 430 MCDA twin pregnancies were included in this study with 152 in the TTTS group, 142 in the sIUGR group, seven in the TAPS group and 129 in the normal MCDA twins group. No further analysis was performed on the TAPS group due to the small sample size. (2) NT discordance in twins of the TTTS group was significantly greater than that in the normal MCDA twins group[(21.5±16.0)% vs (14.6±13.5)%, t=－3.533, P<0.001]. The area under ROC curve (AUC) of TTTS predicted by NT discordance was 0.649. Stratified analysis showed that TTTS was best predicted when NT discordance was 20% with the sensitivity of 57.9% and specificity of 70.6%. (3) The sIUGR group had greater discordance in CRL and NT and higher UCI discordance than the normal MCDA twins group [NT: (27.8±21.3)% vs (14.6±13.5)%, t=－5.556, P<0.001; CRL: (8.6±6.9)% vs (5.4±4.4)%, t=－3.144, P=0.002; UCI: 47.9% (68/142) vs 13.9% (18/129), χ2=35.929, P<0.001]. The AUC of sIUGR was 0.675 predicted by NT discordance and 0.649 by CRL discordance. Stratified analysis showed that NT discordance of 20% and CRL discordance of 10% were the best prediction for sIUGR with the sensitivity of 53.1% and 34.7% and specificity of 72.1% and 83.8%, respectively. Multivariate logistic regression analysis suggested that UCI discordance was the risk factor for sIUGR ( OR=7.165, 95% CI : 2.637-19.472). Conclusions MCDA twins with NT discordance greater than 20% during early pregnancy are at increased risk for TTTS. CRL discordance greater than 10%, NT discordance greater than 20% and abnormal UCI are risk factors for sIUGR.
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Objective To explore the value of chromosome microarray analysis (CMA) in determining the genetic etiology of fetuses with increased nuchal translucency (NT) but normal karyotype. Methods Amniocentesis, karyotype analysis and CMA were performed to singleton pregnant women with increased fetal NT ( ≥ 3.0 mm) in early pregnancy (11+1-13+6 gestational weeks) at Shenzhen Maternity and Child Healthcare Hospital from March 2015 to December 2017. A total of 339 fetuses with normal G banding karyotype analysis were recruited retrospectively. Peripheral blood samples were collected for CMA in parents whose fetuses were detected with pathogenic copy number variations (CNVs) or variants of uncertain significance (VUS). Descriptive analysis was used for CMA results. Moreover, Pregnancy outcomes and postnatal conditions of fetuses with abnormal CNVs were followed up. Results Pathogenic CNVs, ranging from 68 kb to 12.636 Mb, were detected in 15 out of the 339 fetuses (4.4%) including four microduplications and 11 microdeletions. Among them, there were eight known microdeletion or microduplication syndromes (nine cases) including Williams-Beuren syndrome, 18p deletion syndrome,Wolf-Hirschhorn syndrome, 22q11 duplication syndrome, 16p11.2 deletion syndrome, 17p13.3 duplication syndrome, 16p11.2 duplication syndrome (one case respectively) and DiGeorge syndrome/velocardiofacial syndrome (two cases). Of the 11 fetuses with VUS, five cases originated from parents with normal phenotype and the identified VUS were benign and the rest six were de novo mutations[1.8%(6/339)]. Of the 15 fetuses with pathogenic CNVs, one was lost to follow-up, four were live born and two of which was found to be growth retardation at the age of two. Among the 11 fetuses with VUS, nine were live born and no abnormality was reported in any cases at one year old. Conclusions For fetus with increased NT and normal karyotype, CMA is able to identify chromosomal microdeletion/microduplication that are not recognized by conventional karyotyping analysis, and may play an important role in prenatal diagnosis and genetic counseling.
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Objective To investigate the prenatal diagnosis and genetic counseling of fetal nuchal fold (NF) thickening.Methods This study retrospectively analyzed 17 fetuses with increased NF detected by prenatal ultrasound examination in Peking Union Medical College Hospital,Peking Union Medical College & Chinese Academy of Medical Sciences from December 1,2016 to December 1,2017.All cases were divided into isolated (isolated group) or non-isolated increased NF group (non-isolated group) according to whether the fetus had concomitant ultrasonographic abnormalities or not.Karyotype and chromosomal microarray analysis (CMA) were performed on all cases.Clinical data,prenatal genetic testing results and pregnancy outcomes were analyzed.Results Of those twelve cases in the isolated group,two were terminated due to the identification of chromosomal abnormalities and pathogenic copy number variations (CNVs) and the fetal autopsy results were consistent with the prenatal diagnosis.The rest 10 pregnancies were all continued including one fetus carrying a variant of unknown significance,which was proved to be a paternal heredity by CMA,and nine without genetic abnormalities and all-these infants were healthy during follow-up.Among the five non-isolated cases,one was diagnosed as trisomy 21 by karyotyping and CMA,and the other four were found to have structural abnormalities under ultrasound scan,but without genetic abnormalities in karyotyping and CMA.And all the five pregnancies were terminated after genetic counseling and three of them chose whole exome sequencing (WES) for further test.One homozygous mutation in CHRNA 1 gene and one de novo mutation in SETD2 gene were found in two cases,respectively,while no abnormality was identified in the other one case.Conclusions Once increased NF were indicated by ultrasound examination,prenatal genetic testing should be offered to the patients,including CMA,regardless of other ultrasonographic abnormalities,and WES should also be offered when necessary.Considering a thickened NF is associated with increased risks of structural defects,a close follow-up with fetal echocardiography and ultrasound is required even the prenatal tests are normal.
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We hereby reported a case of false negative non-invasive prenatal screening (NIPS) for trisomy 18. The fetus with increased nuchal translucency (3.2 mm) detected by ultrasound scan at 13+4 gestational weeks received NIPS and the result was negative in chromosomes 21, 18 and 13. A routine ultrasound examination at 22 weeks of gestation revealed multiple anomalies and a second NIPS was offered, which showed a negative result again. The pregnancy was terminated at 22+3 weeks. Multiple fetal and placental biopsies were collected for chromosome analysis using copy number variation sequencing based on high-throughput sequencing and fluorescence in situ hybridization. The fetal karyotype was shown to be 47,XY,+18 in fetal tissues (skin and liver) and umbilical cord, while no chromosomal abnormalities was detected at or near the center of the fetal and maternal surface of the placenta. Results of the chromosomal analysis along the edges of the fetal and maternal surfaces of the placenta were Chr18:47,XY,+18[60]/46,XY[40] and Chr18:47,XY,+18[35]/46,XY[65], respectively. We inferred that placental mosaicism was the cause of the false negative NIPS result. Therefore, genetic counseling before and after NIPS is necessary. Follow-up ultrasound is important for NIPS-negative patients. Invasive prenatal diagnosis is recommended when abnormal ultrasound markers with possible genetic etiology were recognized.
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Abstract Objective The main objective of this study was to examine the diagnostic performance of the first-trimester combined test for aneuploidies in unselected pregnancies from Rio de Janeiro and compare it with the examples available in the literature. Methods We investigated 3,639 patients submitted to aneuploidy screening from February 2009 to September 2015. The examination is composed of the Fetal Medicine Foundation risk evaluation based on nuchal translucency evaluation, mother's age, presence of risk factors, presence of the nasal bone and Doppler of the ductus venous in addition to biochemical analysis of pregnancy-associated plasma protein A (PAPP-A) and beta-human chorionic gonadotropin (β-hCG) markers. The cut-off point for high risk for aneuploidies was defined as greater than 1:100, with intermediate risk defined between 1:100 and 1:1,000, and low risk defined as less than 1:1,000. The variable aneuploidy was considered as a result not only of trisomy of chromosome 21 but also trisomy of chromosomes 13 and 18. Results Excluding the losses, the results of 2,748 patients were analyzed. The firsttrimester combined test achieved 71.4% sensitivity with a 7.4% false-positive (FP) rate, specificity of 92.6%, positive predictive value (PPV) of 6.91% and negative predictive value (NPV) of 99.76%, when the cut-off point considered was greater than 1:1,000. Through a receiving operating characteristics (ROC) curve, the cut-off point that maximized the sensitivity and specificity for the diagnosis of aneuploidies was defined as 1:1,860. When we adjusted the false-positive (FP) rate to 5%, the detection rate for this analysis is 72.7%, with a cut-off point of 1:610. Conclusion The combined test of aneuploidy screening showed a detection rate inferior to those described in the literature for a higher FP rate.
Resumo Objetivo O objetivo principal deste estudo foi examinar o desempenho diagnóstico do rastreio combinado de aneuploidias do primeiro trimestre em gestações não selecionadas do Rio de Janeiro e compará-lo com os exemplos disponíveis na literatura. Métodos Investigamos 3.639 pacientes submetidas à triagem para aneuploidia, de fevereiro de 2009 a setembro de 2015. O exame é composto pela avaliação do risco da FetalMedicine Foundation combase na avaliação da translucência nucal, idade da mãe, presença de fatores de risco, presença de osso nasal e Doppler do ducto venoso, além da análise bioquímica dos marcadores proteína A plasmática associada à gravidez (PAPP-A) e gonadotrofina coriônica humana-beta (β-hCG). O ponto de corte para alto risco de aneuploidias foi definido como superior a 1:100, para risco intermediário foi definido entre 1: 100 e 1: 1.000 e para baixo risco foi definido como inferior a 1:1.000. A variável aneuploidia foi considerada não apenas como resultado da trissomia do cromossomo 21, mas também da trissomia dos cromossomos 13 e 18. Resultados Excluindo as perdas, foram analisados os resultados de 2.748 pacientes. O teste combinado do primeiro trimestre alcançou 71,4% de sensibilidade com uma taxa de falsos positivos (FPs) de 7,4%, especificidade de 92,6%, (valor preditivo positivo) VPP de 6,91% e (valor preditivo negativo) VPN de 99,76%, quando o ponto de corte considerado foi maior que 1:1.000. Através de uma curva de característica de operação do receptor (COR), o ponto de corte que maximizou a sensibilidade e especificidade para o diagnóstico de aneuploidias foi de 1:1.860. Quando corrigimos a taxa de FP para 5%, a taxa de detecção para esta análise é de 72,7%, com um ponto de corte de 1:610. Conclusão O rastreio combinado de aneuploidia mostrou uma taxa de detecção inferior à descrita na literatura para uma maior taxa de FP.
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Humans , Female , Adolescent , Adult , Young Adult , Prenatal Diagnosis/methods , Algorithms , Aneuploidy , Pregnancy Trimester, First , Brazil , Risk , Predictive Value of Tests , Sensitivity and Specificity , Middle AgedABSTRACT
Objective To investigated the clinical value of chromosomal microarray analysis (CMA)in fetuses with increased nuchal translucency(NT). Methods Totally 101 cases out of 19261 singleton fetuses who underwent the first trimester(11-13+6 weeks)ultrasound examination from January 2015 to June 2017 at First Affiliated Hospital of Sun Yat-sen University were diagnosed with NT ≥2.5 mm and underwent invasive prenatal test for fetal karyotype and CMA. According to the combination of other ultrasound abnormalities,the cases were divided into isolated group(67.3％, 68 / 101)and complicated group(32.7％, 33/101). In addition, the cases were divided into 5 groups according to the thickness of NT,2.5-2.9 mm(borderline thickening;16.8％, 17/101), 3.0-3.4 mm(33.7％, 34/101), 3.5-4.4 mm(16.8％, 17/101),4.5-5.4 mm(15.8％, 16/101),and ≥5.5 mm(16.8％, 17/101). Chi square test was used to detect the different rates of other combined ultrasound abnormalities and abnormal chromosome between 5 groups. Results The median thickness of NT was 3.4 mm(2.5-8.5 mm). And 32 cases(31.7％, 32/101)had abnormal karyotype. There was a significant difference in the frequency of abnormal karyotype between the isolated and the complicated group(20.6％ vs 54.5％, P<0.01). Among 69 cases(68.3％,69/101) of normal karyotype, 3 cases(4.3％, 3/69)were detected with pathogenic copy number variation(CNV) by CMA. Thirty-five cases with chromosomal abnormalities(include abnormal karyotype and pathogenic CNV), there was a significant difference in the frequency of chromosomal abnormalities between the isolated and the complicated group(23.5％ vs 57.6％, P=0.001). The median age of pregnant women in 5 groups was 35 years(24-39 years),33 years(23-46 years),31 years(21-46 years),33 years (21-41 years) and 35 years (21-43 years). The rates of chromosomal abnormalities increased with the increase of NT thickness. There was significant difference in the incidence of associated chromosomal abnormalities among 5 groups(P<0.05). Comparative analysis within the 5 groups, the incidence of associated chromosomal abnormalities between NT 2.5-2.9 mm and ≥5.5 mm was significantly different (P=0.005), while the differences between the other groups were not significant(P>0.05). Conclusions There is a high risk of fetal chromosomal abnormalities in borderline NT thickening (2.5-2.9 mm)at advanced maternal age, but the pathogenic CNV is not detected. Chromosomal microdeletion or microduplication could be further detected in the NT thickening(≥3.0 mm)fetuses with normal karyotype by chromosome microarray analysis, while the positive rate is relatively low, and the variants of unknown significance might be detected.
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Objective To analyze prognosis-related risk factors of first trimester cystic hygroma (CH)fetuses in which nuchal translucency(NT)was found to be thickened. Methods Tolly 216 singleton pregnancies in which fetal NT≥3.0 mm at the 11～13+6 weeks scan accepted invasive prenatal diagnosis in Beijing Gynecology and Obstetrics Hospital, Capital Medical University, from January 2014 to December 2015 were collected. A total of 164(75.9％, 164/216)single fetuses with complete data were included, they were classified into two groups, namely'CH'and'increased NT'which without CH. And 40 pregnancies (24.4％, 40/164)presented with CH group, 124 pregnancies(75.6％, 124/164)were with increased NT group. The chromosome karyotype abnormality, major organ structure malformation and adverse outcome were compared between the two groups. Logistic regression analysis was used to investigate the effect of increased NT thickness, the presence of septa in CH on abnormal karyotype, major congenital anomaly and adverse outcome. Results (1)The incidence of fetal abnormal karyotype [55.0％(22/40)vs 29.0％(36/124)], major organ anomalies [45.0％(18/40)vs 25.8％(32/124)], and adverse outcome [92.5％(37/40)vs 50.8％(63 / 124)] were significantly different(all P<0.05)between the CH group and the increased NT group.(2)NT measurement was significantly higher in the CH group than that in the increased NT group (8.32 vs 5.06 mm, P<0.01).(3)Logistic analysis revealed that NT thickness was the significant risk factor in the prediction of adverse outcome for CH fetuses in first trimester. The risks of chromosomal defect, major congenital anomaly and adverse outcome increased 1.171, 1.192 and 1.913-fold(all P<0.05)with 1.0 mm increased NT thickness, while the presence of septa in CH didn't increase the risks of above(all P>0.05). Conclusions The perinatal outcome of CH is poor. The poor outcome of CH is closely attributed to thickened NT, and the presence of septa in CH does not increase the risk of adverse outcome for CH fetuses.
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Objective To explore the clinical value of intracranial translucency (HT) in open spina bifida at 11-13 +6 weeks of gestation.Methods Abdominal ultrasound was performed in 200 cases of normal fetus and 6 cases of confirmed open spina bifida at 11-13 +6 weeks of gestation to compare the morphology of IT,diencephalon and midbrain.Results Fetal IT was readily recognized in all 200 normal cases,with diencephalons and midbrain showing number "8" shape.In 6 cases of open spina bifida,fetal IT cannot be identified,and the expected " 8" shape of diencephalon and midbrain was distorted.During 11-13 +6 weeks of pregnancy,the fetal brain is caused by intracranial negative pressure,resulting in morphological changes in the intracranial hyaline,diencephalon and mesencephalon.Conclusions Fetal brain characteristics including intracranial translucency and the shape of diencephalon and midbrain in 11-13 +6 weeks gestation are valuable ultrasound screening indicators for opens pina bifida.
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Objective@#To evaluate the value of non-invasive prenatal testing (NIPT) in pregnancies with anomaly in prenatal screening. @*Methods@#This was a retrospective study of 2 837 singleton pregnancies who performed NIPT indicated by isolated anomaly in prenatal screening at Guangdong Women and Children Hospital between November 2014 and August 2016. All pregnancies were divided into 3 groups by single indication: advanced maternal age ( AMA, ≥35), abnormal multiples of the median (MoM) in standard screening, increased nuchal translucency thickness (NT, 2.5-3.0 mm). High risk results were verified by prenatal diagnosis. Low risk cases were followed by a 22-26 week anatomical ultrasound examination. All of the cases were followed up and the performance of NIPT for every single indication was evaluated. @*Results@#There were total of 2 837 pregnant women who underwent NIPT. Twenty-five of 2 448 pregnancies indicated by AMA had high risk results, among which 17 were confirmed by invasive genetic testing, except 1 case rejecting prenatal diagnosis. In 351 pregnant women with abnormal MoM, NIPT found 3 cases of sex chromosome aneuploidies (SCA) and 2 of them were validated by invasive prenatal diagnosis. Increased NT group included 38 cases, NIPT found 1 case of trisomy 21 which was consistent with karyotype analysis. For common aneuploidies and SCA, the performance of NIPT in the pregnant women who indicated by AMA, abnormal MoM and increased NT were as the follows: the sensitivity were 17/17, 2/2 and 1/1 respectively, the specificity were 99.7% (2 423/2 431), 99.7% (348/349) and 100%(37/37), the positive predictive value were 68% (17/25), 2/3 and 1/1, the negative predictive value were 100% (2 423/2 423), 100% (348/348) and 100% (38/38), respectively. By follow-up survey, a total of 8 cases of abnormal fetus were recorded in NIPT low-risk women, including 5 cases of termination of pregnancy due to abnormal ultrasound findings, 2 cases of abortion as a result of severe obstetric complications and 1 case of stillbirth. @*Conclusions@#To the pregnant women who indicated by advanced maternal age, abnormal MoM and increased NT (2.5-3.0 mm), NIPT had satisfactory performance for common aneuploidies, and also had potential value for SCA, resulting in a significant reduction in diagnostic procedures. However, for NIPT low-risk pregnancies, routine antenatal examination and anatomical ultrasound detection would be highly necessary to avoid missing abnormal fetuses.(Chin J Lab Med, 2018, 41: 509-513)
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Nuchal translucency is an important indicator of an aneuploid fetus in prenatal diagnostics. Previously, only the presence of aneuploid could be confirmed by conventional karyotyping of fetuses with thick nuchal translucency. With the development of genetic diagnostic techniques, however, it has been reported that subtle variations not detectable by conventional karyotyping might occur in cases of pathologic clinical syndrome in euploid fetuses. One of the newer, high-resolution genetic methods in the prenatal setting is chromosomal microarray. The possible association between nuchal translucency thickness with normal karyotype and submicroscopic chromosomal abnormalities detectable by microarray has been studied. How and when to apply microarray in clinical practice, however, is still debated. This article reviews the current studies on the clinical application of microarray in cases of increased nuchal translucency with normal karyotype for prenatal diagnosis.
Subject(s)
Aneuploidy , Chromosome Aberrations , Comparative Genomic Hybridization , Fetus , Karyotype , Karyotyping , Microarray Analysis , Nuchal Translucency Measurement , Prenatal DiagnosisABSTRACT
A first-trimester ultrasound scan has become an essential part of antenatal care. The Korean Society of Ultrasound in Obstetrics and Gynecology held a first-trimester ultrasound forum on April 5, 2014. The forum aimed to present an updated review of the literature on the topic of first-trimester ultrasound in specific lectures and to host a panel discussion on several important issues regarding first-trimester scans. The forum provided evidence- and consensus-based best practice patterns for obstetricians in Korea. Here, we report the review and checklists presented from the forum.
Subject(s)
Female , Humans , Pregnancy , Checklist , Gynecology , Korea , Lecture , Nuchal Translucency Measurement , Obstetrics , Practice Guidelines as Topic , Pregnancy Trimester, First , UltrasonographyABSTRACT
Fundamento: la evaluación mediante ultrasonido de la anatomía embrionaria desde edades precoces permite la detección de embarazos con riesgo de cromosomopatías, con importante valor agregado pues la edad materna avanzada aislada como único indicador de riesgo no es suficiente. Objetivo: evaluar resultados de la medición de translucencia nucal en el ultrasonido del primer trimestre de gestación como marcador sonográfico de cromosomopatías. Métodos: se estudió un universo de 29 334 embarazadas, desde septiembre de 2006 hasta diciembre de 2010. Se evaluó el comportamiento general del marcador sonográfico considerando los años y la edad materna. Se determinó la efectividad de la translucencia nucal aumentada en la detección indirecta de productos con cromosomopatías mediante los parámetros habituales. Resultados: con los años disminuyó el número neto de translucencias nucales aumentadas y la cantidad absoluta de cariotipos prenatales realizados pero aumentó su proporción y la de los cariotipos prenatales positivos entre las mujeres con translucencia nucal aumentada. Entre los 71 fetos con aumento de la translucencia nucal, fueron confirmados por otros elementos del programa prenatal siete cromosomopatías, con una sensibilidad de la translucencia aumentada aislada para su detección de 14,6 %; especificidad de 99,8 %; los valores predictivos positivos fueron de 18,4 % y los negativos de 99,9 %. Se obtuvieron tasas de falsos positivos muy bajos.Conclusiones: la elevada especificidad la reafirma como un buen marcador precoz de riesgo de cromosomopatías, sobre todo síndrome de Down y trisomía 18, que conlleva a una tasa mínima de indicación de procedimientos obstétricos invasivos e incremento extra en la detección de defectos fetales.
Background: assessment of embryonic anatomy by ultrasound since early ages leads to the detection of pregnancies at risk for chromosomal abnormalities. Advanced maternal age alone is not enough. Objective: to assess the results of the nuchal translucency measurement at the first trimester ultrasound as a sonographic marker of chromosomal abnormalities.Methods: a sample of 29 334 pregnant women was studied from September 2006 to December 2010. General performance of the sonographic marker was assessed taking into account the years and maternal age. Effectiveness of increased nuchal translucency in the indirect detection of chromosomal abnormalities was determined using the common parameters. Results: the net number of increased nuchal translucencies diminished over the years, as well as the absolute amount of prenatal karyotypes performed; but its proportion increased along with the positive prenatal karyotypes among women with increased nuchal translucency. Among the 71 fetuses with increased translucency, seven cases of chromosomal abnormalities were confirmed by other elements of the prenatal program. The sensitivity of the isolated nuchal translucency was 14.6%; specificity was high (99.8%); positive and negative predictive values were 18.4% and 99.9%, respectively. Rates of false positives were very low. Conclusions: high specificity reaffirms nuchal translucency as a good early marker of risk for chromosomal abnormalities, particularly Down syndrome and Trisomy 18, with a minimum rate of indications for invasive testing and an extra increase in the detection of fetal defects.
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Objective To evaluate the detection rate of congenital heart defect (CHD) during the first trimester screening for chromosomal abnormalities,the role of ultrasound soft markers including increased nuchal translucency (NT),tricuspid regurgitation (TR) and abnormal ductus venosus (DV) flow in the screening for cardiac anomalies was also investigated.Methods From January 2009 to January 2012,4 673 fetuses were scanned at 11-14 weeks at Department of Fetal Medicine,the First Affiliated Hospital of Jinan University.The ultrasound findings and follow up outcomes were recorded,False-positive rate of different first-trimester ultrasound markers for the detection of CHD was calculated,sensitivity of the markers for all major CHD was calculated as well.Results There was a significant association between major CHD and first trimester ultrasound markers.(1) Overall findings:among the 4 673 fetuses,31 fetuses were diagnosed CHD prenatally,17,12 and 2 of which were detected in the first,second and third trimester,respectively.In 22 of the 31 CHD cases,invasive procedure was performed,fetal karyotype was abnormal in 12 cases,including triosmy 21 (5 cases),trisomy 18 (2 cases),trisomy 13 (2 cases),Turner syndrome (2 cases) and pericentric inversion of chromosome 9 (1 cases).(2) NT measurement and prenatal detected CHD:in 4 673 cases,NT measurement between 95th-99th percentile were present in 206 (4.41％),5 cases were diagnosed CHD prenatally,in 4 of 5 cases were detected in first trimester; NT measurement ＜ 95th percentile were present in 4 430(94.80％),16 cases were diagnosed CHD prenatally,in 5 of 16 cases were detected in first trimester; NT measurement ＞ 99th percentile (＞ 3.5 mm) were present in 37 (0.79％,37/4 673),10 cases were diagnosed CHD prenatally,in 8 of 10 cases were detected in first trimester.(3) TR and inverted a-wave at the DV and prenatal detected CHD:among 4 673 cases,TR or inverted a-wave at the DV were present in 51 (1.09％),98 (2.10％) respectively.TR was present in 8 of 31 CHD cases,inverted a-wave at the DV was present in 7 of 31 CHD cases.(4)Sensitivity of different first trimester ultrasound markers for detection of major CHD cases:in 31 CHD cases diagnosed prenatally,23 eased were defined as major CHD.Sensitivity of at least one of the ultrasound narkers,NT measurement between 95th-99th percentile,＞ 99th percentile(＞ 3.5 mm),TR or inverted a-wave at the DV for detection of major CHD eases was 74％ (17/23),22％ (5/23),39％ (9/23),35％ (8/23),30％ (7/23),respectively.(5) Specificity of different first trimester ultrasound markers for detection of CHD cases:specificity of NT measurement between 95th-99th percentile,＞ 99th percentile(＞ 3.5 mm),TR or inverted a-wave at the DV for detection of major CHD cases was 4.30％ (201/4 673),0.58％ (27/4 673),0.92％ (43/4 673),1.94％ (91/4 673).Conclusions Routine first trimester soft markers for chromosomal abnormalities screening combined with cardiac assessment can detect quite a number of major heart defects.Increased NT,TR and abnormal DV flow can be important indicators for echocardiography,which is favorable to early prenatal diagnosis of CHD.