ABSTRACT Nuchal Translucency as a method of First Trimester Screening for Aneuploidy in a South African population Background Chromosomal abnormalities constitute 15% of congenital abnormalities and 50% of pregnancy losses. Twenty-five percent of these will be Trisomy 21. Down’s syndrome has a birth incidence of 2 per 1000 and constitutes 25% of severe mental handicap in the developed world. Whereas the risk assessment focuses on Trisomy 21, the fetuses that screen positive are also known to contain other defects, which include anomalies such as cardiac defects, diaphragmatic hernias, neuromuscular disorders, and rare genetic syndromes. Objective To determine the effectiveness of nuchal translucency (NT) screening in predicting aneuploidy and structural abnormalities in a South African population Setting Chris Hani Baragwanath Hospital Fetal Medicine Unit Study design Descriptive Study Methodology The Fetal Medicine Unit database was reviewed and the records of patients who had undergone NT screening between July 2003 and July 2005 were retrieved. There were no exclusions. An adjusted risk was derived from the combination of age-related risk and the risk derived from nuchal translucency screening. A positive screen was denoted by an adjusted risk of more than 1/300 and a negative screen was denoted by an adjusted risk of less than 1/300. Results A total of 428 patients had first trimester screening during this period. Thirteen patients (3%) were lost to follow up. Of the 415 cases that were analyzed, 57 patients screened positive and 356 patients screened negative. In addition, 2 fetuses with acrania were detected. The mean age for both groups of patients was 30.1 years. The crown-rump length of fetuses with a positive screen was statistically significantly shorter than fetuses that screened negative. Of the 57 patients that screened positive 24 elected to have chorionic villus sampling (CVS) which resulted in the detection of 6 chromosomal abnormalities and 2 structural abnormalities. Of the remaining 356 patients, who had screened negative, 2 had an increased adjusted risk, and one chromosomal abnormality was detected in this group. Of the remaining 354 patients, 8 elected to have CVS because of a previous history of chromosomal abnormality. All of them proved to be normal. Conclusions The use of such screening has enabled prenatal karyotyping to be focused on pregnancies at highest risk for chromosomal abnormalities regardless of age.

No description available.

Orientador: Marcus Antônio Rossi Feliciano / Resumo: Os objetivos deste estudo foram avaliar as características ultrassonográficas (modo-B e da elastografia) das estruturas do sistema nervoso central (SNC) de fetos caninos, como método complementar para predizer a idade gestacional, avaliar o desenvolvimento dos conceptos, estabelecer padrões de normalidade e auxiliar no diagnóstico de anormalidades gestacionais. Foram utilizadas 26 cadelas braquicefálicas, da raça Bulldog Inglês, com idade entre um e quatro anos e meio. Os exames ultrassonográficos foram realizados em três momentos da gestação, aos 34, 49 e 60 dias, com o aparelho ACUSON S2000/SIEMENS e transdutor multifrequencial matricial e linear de 9,0 MHz. Foram avaliados três fetos de cada fêmea. Verificou-se a presença da massa cerebral fetal, seu formato em corte transversal, ecotextura e ecogenicidade, presença e mensuração da translucência nucal (TN). O cerebelo foi avaliado em corte transversal, verificando-se seu formato, ecotextura, ecogenicidade e comprimento do seu eixo maior. A elastografia foi aplicada ao tecido fetal cerebral e cerebelar obtendo-se velocidades médias de cisalhamento (m/s) e elastogramas. O delineamento experimental foi em blocos casualizado (cadelas), com parcelas subdivididas no tempo (dias gestacionais), e a análise estatística foi realizada pela análise de variância (ANOVA) com medidas repetidas no tempo. Das 26 ninhadas estudadas, 18 tiveram somente fetos saudáveis, 4 apresentaram fetos com anasarca, 3 apresentaram fetos com defeitos da p... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objectives of this study were to evaluate the ultrasound (B-mode and elastography) characteristics of canine fetal central nervous system structures as complementary method to predict gestational age, to evaluate the development of the fetuses, to establish normality patterns and to assist in diagnosis of gestational abnormalities. Twenty-six brachycephalic female dogs of the English Bulldog breed, aged between one and four and a half years were used. Ultrasound examinations were performed at three gestational moments, at 34, 49 and 60 gestation days, with the ACUSON S2000 / SIEMENS device and a 9.0 MHz matrix and linear multifrequency transducer. Three fetuses of each female were evaluated. The presence of fetal brain mass, its cross-sectional shape, echotexture and echogenicity, presence and measurement of nuchal translucency (TN) were verified. The cerebellum was evaluated in cross-section, verifying its shape, echotexture, echogenicity and length of its major axis. Elastography was applied to the fetal brain and cerebellar tissue to obtain mean velocities and elastograms. The experimental design was randomized in blocks (bitches) with plots subdivided in time (gestational days) and statistical analysis was performed by analysis of variance (ANOVA) with repeated measures over time. Of the 26 litters studied, 18 had only healthy fetuses, 4 had fetuses with anasarca, 3 had fetuses with abdominal wall defects, and 1 had both types of alterations. The TN was higher (P=0.02... (Complete abstract click electronic access below) / Mestre

目前廣泛應用于胎兒醫學的唐氏綜合症篩查法，即結合早孕期胎兒頸項透明層的超聲檢查，及母體血清生化指標的綜合篩查法。頸項透明層是指在早孕期利用超聲檢測到的胎兒頸后的皮下積水，其作為預測胎兒異常的一項重要“軟指標，其臨床意義，尤其是與胎兒染色體異常及器官結構異常之間的關係，逐漸得到深入的認識，但其形成機制尚未明確。現在已知有一百餘種畸形及遺傳綜合征與胎兒頸項透明層增厚相關，但其染色體異常譜系，尤其是亞顯微的染色體異常仍有待明確。大部分頸項透明層增厚但核型正常的胎兒預後良好，但約3-10%的這部分胎兒會伴有畸形或出生后的神經智力發育缺陷。而傳統核型分析無法檢測到亞顯微的染色體異常，從而無法判斷這部分核型正常卻伴有缺陷的胎兒是否因為這類染色體異常而致病。 / 微陣列比較基因組雜交芯片作為檢測兒童發育遲緩者及器官結構異常原因的重要手段已廣泛應用于臨床。在染色體核型正常的胎兒中，若伴有器官結構異常的胎兒，5-12%被檢出與該畸形相關的微缺失及微重複；若僅伴有孕婦高齡或唐氏篩查高危，則微缺失及微重複檢出率約1%。 / 該課題旨在研究頸項透明層增厚但核型正常的胎兒中，染色體拷貝數變異發生的頻率及頻譜；評估微陣列比較基因組雜交芯片在協助臨床判斷胎兒預後中的作用。因此，我們開展該多中心隊列研究，通過納入449例頸項透明層厚度≧3.5 mm但正常核型胎兒的，檢測其染色體拷貝數變異，監測并記錄其圍產、產後及新生兒期情況。微陣列比較基因組雜交芯片總共檢出2.8%的異常拷貝數變異，其大小範圍為0.1 kb至18Mb。在伴有器官結構異常的胎兒組中，異常拷貝數變異檢出率達7.8%。對於頸項透明層厚度≧4.0 mm的胎兒，異常拷貝數變異檢出率可達7.3%。 / 對於頸項透明層增厚的胎兒，致病拷貝數變異暫未發現特定的頻譜。但，該研究中發現重複的致病拷貝數變異，如22號染色體長臂1區1帶的微重複或微缺失，2號染色體長臂2區2帶的微缺失。未在3號、7號、12號、13號、18號、20號、21號或Y染色體上發現與胎兒頸項透明層增厚相關的致病拷貝數變異。 / 頸項透明層增厚的胎兒79.3%預後良好；若經微陣列比較基因組雜交芯片未檢出致病拷貝數變異，則81.2%預後良好。如果僅頸項透明層增厚不伴有結構異常的胎兒，經微陣列比較基因組雜交芯片未檢出致病拷貝數變異，則93.5%預後良好。 / 綜上所述，微陣列比較基因組雜交芯片顯著提高了致病拷貝數變異的檢出率。可考慮將微陣列比較基因組雜交芯片作為頸項透明層厚度≧4.0 mm的胎兒染色體異常檢查的首要方法。對於僅頸項透明層增厚不伴有結構異常的胎兒，且經微陣列比較基因組雜交芯片未檢出致病拷貝數變異，絶大部分預後良好。對於頸項透明層增厚的胎兒，致病拷貝數變異暫未發現特定的頻譜，但發現重複出現的致病拷貝數變異。通過初步的基因本體分析及基因通路分析，神經嵴細胞的分化遷徙功能異常可作為今後研究頸項透明層增厚的病理生理機制的方向。 / Measurement of nuchal translucency (NT) has been recognized as a sensitive marker for fetal chromosomal disorders for more than a decade, and is presently used as a routine first-trimester screening test. Although over 100 abnormalities and genetic syndromes have been reported to be associated with increased NT, these associations have not been fully explored and the relevant spectrum of associated submicroscopic chromosomal abnormalities has not been sufficiently investigated. The majority of euploid fetuses with increased NT have a good outcome, but around 3-10% of fetuses present with structural or neurodevelopmental abnormalities postnatally. A range of genetic syndromes has been reported, many of which are linked to submicroscopic chromosomal abnormalities that are typically missed by conventional karyotyping. / Microarray-based comparative genomic hybridization (arrayCGH) has been applied as the first-tier diagnostic tool for the evaluation of developmental delay and structural malformations in children. In fetuses with a normal karyotype, microarray analysis revealed clinically relevant deletions or duplications in 5-12% with a structural anomaly and in about 1% of those whose indications were advanced maternal age or positive screening results. / The objectives of this study were to delineate the frequency and spectrum of pathogenic chromosome copy number variants (CNVs) among fetuses with increased NT and normal karyotype; to evaluate the role of arrayCGH to predict the prognosis of the high NT fetuses; to explore the genotype-phenotype correlations of increased NT. Therefore, a multi-centre cohort of 449 fetuses with NT ≧3.5 mm and normal karyotype were further investigated by arrayCGH. Antenatal surveillance, pregnancy outcome and paediatric follow up were documented. ArrayCGH detected abnormal CNVs in 2.8% (14 of 449) of the fetuses with high NT; the size of CNVs ranged from 0.1 kb to 18Mb. Among fetuses with major congenital abnormalities the incidence of abnormal CNV reached 7.8% (4 of 51). By adjusting the NT to ≧4.0 mm as the referral indication, 7.3% (14 of 192) of the fetuses would have abnormal arrayCGH results. The spectrum of pathogenic CNVs found associated with increased NT was diverse. However, there were recurrent ones such as the deletions or duplications at chromosomal region 22q11, and deletions in ZEB2. There was no pathogenic CNV related with increased NT found in chromosomes 3, 7, 12, 13, 18, 20, 21, or Y. The total normal outcome rate of euploid fetuses with an increased NT was 79.3%; for fetuses with normal arrayCGH results 81.2% had a normal outcome. In fetuses with isolated increased NT, normal arrayCGH results predict a favorable prognosis of 93.5%. / In conclusion, arrayCGH significantly increased the diagnostic yield of pathogenic CNVs. In clinical practice arrayCGH may be considered as the first tier investigation in fetuses with an increased NT more than 4.0 mm. In cases with an isolated increased NT with normal arrayCGH results the pregnancy outcome is likely to be favorable. The spectrum of abnormal CNVs found by arrayCGH is diverse but there are recurrent cases such as del/dup 22q11 and del ZEB2. Our preliminary gene ontology and pathway analysis showed that gene pathways related to neural crest cells may be considered as a future study for physiopathologic mechanisms of NT. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Huang, Jin. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 106-120). / Abstracts also in Chinese.

This work deals with displaying and measuring ultrasonic markers of congenital defects of the fetus in first trimester of pregnancy. Background research of ultrasonic markers was based on the studies of prof. Kypros Nicolaides (Great Britain), the president of the Fetal Medicine Foundation. This work contains a brief description of diagnosing of congenital defects during all three trimesters, and lists in detail defects that can be diagnosed properly during first trimester, as well as methods of calculating the risk of chromosomal abnormalities. In the next parts of this work, there are descriptions of methods used to improve results while measuring nuchal translucence (NT) strongest marker of Down syndrome in first trimester. The imaging capabilities of ultrasound devices were tested. Using scanned images, the influence of different display parameters on the resolution could be determined. Furthermore, using recommendations of the FMF, algorithms for adjusting correct slice of fetus and automatic measurement NT were designed and tested. A program application was designed that enabled testing of those algorithms on real images and calculating risks of chromosomal abnormalities from CRL and NT value. Designed algorithms were tested on real images. The program application, in witch the algorithms for measuring NT (NT detection algorithms) are included, was created.

A pesquisa de marcadores ultrassonográficos no segundo trimestre da gestação, após rastreamento combinado no primeiro, parece elevar substancialmente as taxas de detecção de Síndrome de Down, mas está amparada na assunção não comprovada de independência entre esses testes. O presente estudo investigou a relação entre a translucência nucal e uma série de marcadores ultrassonográficos no segundo trimestre. A medida da translucência nucal no primeiro trimestre era seguida pela realização da ultrassonografia morfológica entre 18 a 23 semanas e 6 dias de gestação, incluindo a pesquisa de três marcadores qualitativos (foco ecogênico intracardíaco, intestino hiperecogênico e defeito estrutural) e as medidas do osso nasal, da prega nucal, do comprimento do úmero, do comprimento do fêmur, do diâmetro anteroposterior das pelves renais e da espessura pré-nasal. Todas as variáveis contínuas foram expressas em múltiplos da mediana para a idade gestacional e os coeficientes de correlação entre a translucência nucal e essas variáveis (após transformação logarítmica) foram calculados. Em seguida, as frequências de marcadores clássicos no segundo trimestre, em casos com translucência nucal normal, foram comparadas àquelas com translucência nucal aumentada, usando pontos de corte definidos em múltiplos da mediana. Em população prospectiva de 1970 casos, a translucência nucal se correlacionou significativamente com todas as variáveis ultrassonográficas do segundo trimestre, em particular, com a prega nucal (r=0.10). Houve frequência significativamente maior de casos com prega nucal aumentada (10,7 versus 2,2%), definida como valor (em MoMs) acima do percentil 97,5, e intestino hiperecogênico (2,4% versus 0,1%) em casos com translucência nucal aumentada. Concluindo, a utilização de razões de verossimilhança baseadas na presença, ou ausência, de marcadores ultrassonográficos no segundo trimestre para modificar o risco calculado, no primeiro trimestre, poderia deteriorar a precisão das estimativas. Técnicas multivariadas por meio de marcadores ultrassonográficos quantitativos seriam opção mais adequada para a implantação de estratégias de rastreamento sequenciais / Genetic sonogram following first trimester combined screening appears to substantially increase detection rates for Down syndrome but it relies on the unproved assumption of independence between these tests. In this study we have investigated the relation of first trimester nuchal translucency to a series of secondtrimester soft markers. Nuchal translucency (NT) measurement in the first trimester was followed by second trimester scan (18-23w+6 days) including search for three categorical soft-markers (intracardiac echogenic foci, hyperechogenic bowel and structural defects) and measurements of nasal bone length, nuchal fold thickness, femur length, humerus length, renal pelvices diameter and prenasal thickness. All continuous variables were expressed in multiples of the medians for gestation (MoMs) and correlation coefficients between log-transformed NT and second trimester variables were calculated. In addition, frequencies of classical soft-markers in cases with increased NT were compared to those with normal NT, using MoMs cutoffs. In a dataset of 1970 cases, NT was significantly correlated (p<0.05) to all second trimester continuous variables, in particular to nuchal fold thickness (r=0.10). There was a higher frequency of cases with second trimester nuchal fold thickness above the 95th centile (10.7% versus 2.2%) and hyperechogenic bowel (2.4% versus 0.1%) in cases with increased NT. In conclusion, straightforward reassessment of risk using likelihood ratios derived from the classical genetic sonogram might lead to inaccurate estimates. Multivariate models using continuous second-trimester variables might be preferable in sequential screening strategies

A pesquisa de marcadores ultrassonográficos no segundo trimestre da gestação, após rastreamento combinado no primeiro, parece elevar substancialmente as taxas de detecção de Síndrome de Down, mas está amparada na assunção não comprovada de independência entre esses testes. O presente estudo investigou a relação entre a translucência nucal e uma série de marcadores ultrassonográficos no segundo trimestre. A medida da translucência nucal no primeiro trimestre era seguida pela realização da ultrassonografia morfológica entre 18 a 23 semanas e 6 dias de gestação, incluindo a pesquisa de três marcadores qualitativos (foco ecogênico intracardíaco, intestino hiperecogênico e defeito estrutural) e as medidas do osso nasal, da prega nucal, do comprimento do úmero, do comprimento do fêmur, do diâmetro anteroposterior das pelves renais e da espessura pré-nasal. Todas as variáveis contínuas foram expressas em múltiplos da mediana para a idade gestacional e os coeficientes de correlação entre a translucência nucal e essas variáveis (após transformação logarítmica) foram calculados. Em seguida, as frequências de marcadores clássicos no segundo trimestre, em casos com translucência nucal normal, foram comparadas àquelas com translucência nucal aumentada, usando pontos de corte definidos em múltiplos da mediana. Em população prospectiva de 1970 casos, a translucência nucal se correlacionou significativamente com todas as variáveis ultrassonográficas do segundo trimestre, em particular, com a prega nucal (r=0.10). Houve frequência significativamente maior de casos com prega nucal aumentada (10,7 versus 2,2%), definida como valor (em MoMs) acima do percentil 97,5, e intestino hiperecogênico (2,4% versus 0,1%) em casos com translucência nucal aumentada. Concluindo, a utilização de razões de verossimilhança baseadas na presença, ou ausência, de marcadores ultrassonográficos no segundo trimestre para modificar o risco calculado, no primeiro trimestre, poderia deteriorar a precisão das estimativas. Técnicas multivariadas por meio de marcadores ultrassonográficos quantitativos seriam opção mais adequada para a implantação de estratégias de rastreamento sequenciais / Genetic sonogram following first trimester combined screening appears to substantially increase detection rates for Down syndrome but it relies on the unproved assumption of independence between these tests. In this study we have investigated the relation of first trimester nuchal translucency to a series of secondtrimester soft markers. Nuchal translucency (NT) measurement in the first trimester was followed by second trimester scan (18-23w+6 days) including search for three categorical soft-markers (intracardiac echogenic foci, hyperechogenic bowel and structural defects) and measurements of nasal bone length, nuchal fold thickness, femur length, humerus length, renal pelvices diameter and prenasal thickness. All continuous variables were expressed in multiples of the medians for gestation (MoMs) and correlation coefficients between log-transformed NT and second trimester variables were calculated. In addition, frequencies of classical soft-markers in cases with increased NT were compared to those with normal NT, using MoMs cutoffs. In a dataset of 1970 cases, NT was significantly correlated (p<0.05) to all second trimester continuous variables, in particular to nuchal fold thickness (r=0.10). There was a higher frequency of cases with second trimester nuchal fold thickness above the 95th centile (10.7% versus 2.2%) and hyperechogenic bowel (2.4% versus 0.1%) in cases with increased NT. In conclusion, straightforward reassessment of risk using likelihood ratios derived from the classical genetic sonogram might lead to inaccurate estimates. Multivariate models using continuous second-trimester variables might be preferable in sequential screening strategies

Abstract The aim of the present study was to evaluate the efficacy of the first trimester screening for Down syndrome (DS) in an unselected low-risk Finnish population. The study involved 4,617 women who attended screening between the 8th and 14th weeks of pregnancy in 1998-2000. They gave a blood sample for the measurement of pregnancy associated plasma protein A (PAPP-A) and free beta human chorionic gonadotrophin (β-hCG). Of these women, 3,178 also had an ultrasound examination for the measurement of fetal nuchal translucency (NT). The risk figure for every screened woman was calculated using a computerized risk figure program. The risk 1 in 250 was used as a cut-off. The subgroup of screen positives comprised 5.8% of the study group. There were 16 DS cases. The combined method (maternal age, NT and the biochemical markers) detected 77% of the affected pregnancies. NT combined with maternal age gave a detection rate of 69%. Serum markers without NT combined with maternal age found 75% of the Down's. In 49 consecutive singleton in-vitro-fertilization pregnancies, the β-hCG value was more often elevated compared to spontaneous pregnancies, increasing the false positive rate. In 67 twin pregnancies, the serum marker levels were approximately double those in singletons. Smoking reduced PAPP-A by 20% making the smokers more likely to get a positive screening result. To determine the impact of the screening on the live born incidence of DS, two historical populations were compared. The first group was screened by second trimester serum samples (β-hCG and AFP) and the second group by first trimester ultrasound examination. When detection rates were at the same level, the second trimester screening reduced the number of live born Down's children more effectively. In conclusion, the first trimester combined method (maternal age, NT, β-hCG and PAPP-A) for Down syndrome screening is efficient in an unselected low risk population. The biochemical screening is not recommended in IVF-pregnancies.

Objetivo: analisar o resultado das gestações e pós-natal dos fetos com translucência nucal (TN) aumentada. Método: Duzentos e setenta e cinco fetos com TN aumentada foram avaliados no setor de Medicina Fetal da Clínica Obstétrica do HC-FMUSP, com análise do cariótipo, ultra-sonografia seriada, ecocardiografias fetal e pós-natal e avaliação clinica genética pós-natal. Resultados: 14,2% apresentaram cariótipos alterados e 85,8% normais. A ultra-sonografia morfológica esteve alterada em 73,1% dos casos com cariótipo anormal e em 24,7% dos normais, destes, um terço apresentou malformações estruturais maiores, sendo 35,7% cardíacas. Resultados gestacionais adversos, como abortamento, óbitos intra-útero e neonatal ocorreram em 76,5% dos fetos com anomalias cromossômicas e em 10,2% com cariótipos normais. A avaliação pós-natal foi realizada em 72,7% das crianças, mostrando-se alterada em 14,8% dos casos. A freqüência de criança viva e saudável diminuiu com a medida da TN, que variou de 37,5%, nos casos com cariótipos normais, a 18,8% com cariótipos desconhecidos, quando a TN foi igual ou maior que 4,5 mm. Conclusão: Quanto maior a TN maior o risco de anomalias cromossômicas e, nos casos com cariótipos normais, maior a freqüência de malformações estruturais, em especial defeitos cardíacos, resultados gestacionais adversos e alterações à avaliação pós-natal / The aim of this study was to evaluate pregnancy and postnatal outcomes in fetuses with increased nuchal translucency thickness (NT). Two hundred seventy five fetuses with increased NT were examined with karyotyping analysys, serial ultrasound scans, ecocardiography and postnatal clinical and genetic evaluation at the Fetal Medicine Unit - Departament of Obstetrics - São Paulo University. The karyotype was abnormal in 14.2% of the cases and normal in 85.8%. At the anomaly scan, 73.1% of the abnormal karyotype and 24.7% of the normal fetuses presented structural abnormalities, one third of these were major malformations with 35.7% of cardiac defects. Adverse pregnancy outcome as miscarriages, intrauterine and neonatal deaths occurred in 76.5% of the abnormal karyotype group and in 10.2% of the normal. 72.7% of the infants with normal karyotype had postnatal examination with 14,8% presenting abnormalities. The chances of having a live and healthy child decreased with increased NT thickness. For NT above 4.5mm this varied from 18.8%, for an unknown karyotype result, to 37.5% for a normal karyotype. The chances of abnormal karyotype increased with NT thickness. In addition, when the karyotype was normal, the frequency of fetal malformations, specially heart defects, adverse pregnancy outcome and postnatal abnormalities increased with NT thickness

Objetivo: analisar o resultado das gestações e pós-natal dos fetos com translucência nucal (TN) aumentada. Método: Duzentos e setenta e cinco fetos com TN aumentada foram avaliados no setor de Medicina Fetal da Clínica Obstétrica do HC-FMUSP, com análise do cariótipo, ultra-sonografia seriada, ecocardiografias fetal e pós-natal e avaliação clinica genética pós-natal. Resultados: 14,2% apresentaram cariótipos alterados e 85,8% normais. A ultra-sonografia morfológica esteve alterada em 73,1% dos casos com cariótipo anormal e em 24,7% dos normais, destes, um terço apresentou malformações estruturais maiores, sendo 35,7% cardíacas. Resultados gestacionais adversos, como abortamento, óbitos intra-útero e neonatal ocorreram em 76,5% dos fetos com anomalias cromossômicas e em 10,2% com cariótipos normais. A avaliação pós-natal foi realizada em 72,7% das crianças, mostrando-se alterada em 14,8% dos casos. A freqüência de criança viva e saudável diminuiu com a medida da TN, que variou de 37,5%, nos casos com cariótipos normais, a 18,8% com cariótipos desconhecidos, quando a TN foi igual ou maior que 4,5 mm. Conclusão: Quanto maior a TN maior o risco de anomalias cromossômicas e, nos casos com cariótipos normais, maior a freqüência de malformações estruturais, em especial defeitos cardíacos, resultados gestacionais adversos e alterações à avaliação pós-natal / The aim of this study was to evaluate pregnancy and postnatal outcomes in fetuses with increased nuchal translucency thickness (NT). Two hundred seventy five fetuses with increased NT were examined with karyotyping analysys, serial ultrasound scans, ecocardiography and postnatal clinical and genetic evaluation at the Fetal Medicine Unit - Departament of Obstetrics - São Paulo University. The karyotype was abnormal in 14.2% of the cases and normal in 85.8%. At the anomaly scan, 73.1% of the abnormal karyotype and 24.7% of the normal fetuses presented structural abnormalities, one third of these were major malformations with 35.7% of cardiac defects. Adverse pregnancy outcome as miscarriages, intrauterine and neonatal deaths occurred in 76.5% of the abnormal karyotype group and in 10.2% of the normal. 72.7% of the infants with normal karyotype had postnatal examination with 14,8% presenting abnormalities. The chances of having a live and healthy child decreased with increased NT thickness. For NT above 4.5mm this varied from 18.8%, for an unknown karyotype result, to 37.5% for a normal karyotype. The chances of abnormal karyotype increased with NT thickness. In addition, when the karyotype was normal, the frequency of fetal malformations, specially heart defects, adverse pregnancy outcome and postnatal abnormalities increased with NT thickness