PURPOSE: To evaluate the effects of the deviation from the mid-sagittal plane, fetal image size, tissue harmonic imaging (THI), and speckle reduction filter (SRF) on the measurement of the nuchal translucency (NT) thickness using Volume NT(TM) software. MATERIALS AND METHODS: In 79 pregnant women, NT was measured using Volume NT(TM). Firstly, the three-dimensional volumes were categorized based on the angle of deviation in 10degrees intervals from the mid-sagittal plane. Secondly, the operator downsized the fetal image to less than 50% of the screen (Method A) and by magnifying the image (Method B). Next, the image was magnified until the fetal head and thorax occupied 75% of the screen, and the NT was measured (Method C). Lastly, NT values were acquired with THI and SRF functions on, with each function alternately on, and with both functions off. RESULTS: The mean differences in NT measurements were -0.09 mm (p<0.01) between two-dimensional (2D) and a deviation of 31-40degrees and -0.10 mm (p<0.01) between 2D and 41-50degrees. The intraclass correlation coefficients (ICC) for 2D-NT and NT according to image size were 0.858, 0.923, and 0.928 for methods A, B, and C, respectively. The ICC for 2D-NT and NT with respect to the THI and SRF were 0.786, 0.761, 0.740, and 0.731 with both functions on, THI only, SRF only, and with both functions off, respectively. CONCLUSION: NT measurements made using Volume NT(TM) are affected by angle deviation from the mid-sagittal plane and fetal image size. Additionally, the highest correlation with 2D-NT was achieved when THI and SRF functions were used.
Adult ; Embryo, Mammalian/*ultrasonography ; Female ; Humans ; Image Enhancement/*methods ; Imaging, Three-Dimensional/*methods ; *Nuchal Translucency Measurement/methods ; Pregnancy ; Sensitivity and Specificity ; Software

This study evaluated the sensitivities and false positive rates of the screening test using ultrasonographic measurement of thickness of nuchal translucency (NT) with different cut-offs for chromosomal aberration in a Korean population. We included 2,570 singleton pregnancies undergoing ultrasound between 11 weeks and 14 weeks of gestation in this study. We analyzed the sensitivities of NT alone for screening chromosomal aberration using three cut-offs -2.5 mm, 3.0 mm, and 95th percentile for each crown rump length (CRL). There were 31 chromosomal aberrations (1.2%) including 12 cases of trisomy 21. The numbers of chromosomal aberrations that were detected by NT with different cut-offs of 2.5 mm, 3.0 mm and the 95th percentile CRL were 22, 18 and 23, respectively. At a threshold of 2.5 mm, the sensitivity and the false positive rate for total chromosomal aberrations were 67.7% and 6.3%, respectively. At 3.0 mm, those were 54.8% and 3.5%, respectively. At the 95th percentile CRL, those were 70.9% and 5.8%, respectively. The use of CRL-dependent cut-offs for nuchal translucency improves the detection of chromosomal aberrations when compared to fixed cut-offs in a Korean population.
Adult ; *Chromosome Aberrations ; Chromosome Disorders/diagnosis ; Comparative Study ; Female ; Fetal Diseases/*diagnosis/genetics ; Humans ; Mass Screening/methods ; Nuchal Translucency Measurement/*methods ; Pregnancy ; Sensitivity & Specificity

OBJECTIVE: To assess the value of chromosomal microarray analysis (CMA) and trio-whole exome sequencing (trio-WES) for fetuses with increased nuchal translucency (NT) thickness. METHODS: Sixty two pregnant women who had visited Urumqi Maternal and Child Care Health Hospital between June 2018 and June 2020 for NT ≥ 3.0 mm at 11 ~ 13⁺⁶ gestational weeks were selected as study subjects. Relevant clinical data were collected. The patients were divided into 3.0 ~ ＜3.5 mm (n = 33) and ≥3.5 mm groups (n = 29). Chromosome karyotyping analysis and chromosomal microarray analysis were carried out. And trio-WES analysis was performed on 15 samples with NT thickening but negative CMA results. The distribution and incidence of chromosomal abnormalities in the two groups were compared by using chi-square test. RESULTS: The median age of the pregnant women was 29 years old (22 ~ 41 years old), the median thickness of NT was 3.4 mm (3.0 ~ 9.1 mm), and the median gestational age at the detection was 13⁺⁴ weeks (11⁺⁵ ~ 13⁺⁶ weeks). Chromosome karyotyping analysis has detected 12 cases of aneuploidies and 1 case of derivative chromosome. The detection rate was 20.97% (13/62). CMA has detected 12 cases of aneuploidies, 1 case of pathogenic CNV and 5 cases of variant of uncertain significance (VUS), with a detection rate of 29.03% (18/62). The aneuploidy rate for the NT ≥ 3.5 mm group was higher than that for the 3.0 ≤ NT < 3.5 mm group [3.03% (1/33) vs. 41.38% (12/29), χ² = 13.698, P < 0.001]. There was no statistically significant difference between the two groups in the detection rate of fetal pathogenic CNV and VUS (χ² = 0.028, P > 0.05). Trio-WES analysis of 15 samples with negative CMA result and no structural abnormality has identified 6 heterozygous variants, including SOS1: c.3542C>T (p.A1181V) and c.3817C>G (p.L1273V), COL2A1: c.436C>T (p.P146S) and c.3700G>A (p.D1234N), LZTR1: c.1496T>C (p.V499A), and BRAF: c.64G>A (p.D22N), respectively. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), all of the variants were rated as VUS. CONCLUSION NT thickening can indicate chromosome abnormality, and CMA and trio-WES may be used for the prenatal diagnosis.
Pregnancy ; Humans ; Female ; Adult ; Infant ; Nuchal Translucency Measurement/methods* ; Prenatal Diagnosis/methods* ; Chromosome Aberrations ; Aneuploidy ; Fetus/diagnostic imaging* ; Ultrasonography, Prenatal ; DNA Copy Number Variations ; Transcription Factors

INTRODUCTIONThis study examines the effectiveness of double-marker analysis for α-fetoprotein (AFP) and β-human chorionic gonadotropin (β-hCG) combined with measurement of nuchal fold thickness (NT) in the detection of Down's syndrome (DS) in Mainland Chinese subjects during second trimester prenatal screening.

MATERIALS AND METHODSWe examined pregnant women with a singleton pregnancy between 15 and 21 weeks of gestation who underwent second trimester screening for DS using double-marker analysis for AFP and β-hCG combined with ultrasound measurement of NT. The combined risk of DS was calculated. A cut-off of 1/270 was used to define a pregnancy at high-risk of DS. Amniocentesis was offered to all patients with high-risk pregnancies.

RESULTSUsing double-marker analysis for AFP and β-hCG in combination with measurement of NT, the detection rate of DS increased from 66.7% to 77.8% when compared with double-marker analysis alone with similar false-positive rates (4.35%, 4.83% respectively). Using receiver operating characteristic curve (ROC) analysis, we determined that the double-marker analysis combined with measurement of NT exhibited an increased area under the curve (AUC) of 0.835 (95% CI: 0.743 to 0.927) when compared to double-marker analysis alone, which had an AUC of 0.748 (95% CI: 0.635 to 0.860). In addition, both methods were more effective than any other single test such as AFP, free β-hCG or NT measurement.

CONCLUSIONSecond trimester prenatal screening using double-marker analysis for AFP and β-hCG combined with measurement of NT is effective for the detection of DS in Mainland Chinese pregnancies.

Adult ; Biomarkers ; China ; Chorionic Gonadotropin, beta Subunit, Human ; blood ; Down Syndrome ; diagnosis ; diagnostic imaging ; Female ; Gestational Age ; Humans ; Mass Screening ; Nuchal Translucency Measurement ; methods ; Pregnancy ; Pregnancy Trimester, Second ; Prenatal Diagnosis ; Risk Assessment ; Young Adult ; alpha-Fetoproteins ; analysis

OBJECTIVETo evaluate the efficiency of first trimester prenatal screening for fetal chromosome abnormality using maternal serum marker test and(or) plus nuchal translucency (NT) in Guangzhou region.

METHODSThe results of prenatal screening were retrospectively analyzed among 43 703 women with singleton pregnancies from January 2007 to September 2012. A total of 43 703 pregnancies between 9 and 13(+6) weeks of pregnancy were collected and analyzed for maternal serum pregnancy-associated plasma protein A (PAPPA), free β -human chorionic gonadotropin (free β -hCG) with or without crown-rump length (CRL). Nuchal translucency was measured by ultrasonographic scan between 11 and 13(+6) weeks of pregnancy. Gestational age was estimated by ultrasonographic scan. The risk values of Down syndrome (DS) and trisomy 18 were calculated using the software Lifcycle. Comparing the difference between the combined screening (PAPPA, free β -hCG and NT) and serum marker screening (PAPPA and free β -hCG).

RESULTSAmong the 43 703 pregnant women, screening showed that 1385 (3.17%) were Down syndrome positive and 55 (0.13%) were trisomy 18 positive. The final outcomes of pregnancy showed that 142 cases presented chromosomal abnormalities, of which 54 cases suffered from Down syndrome, 13 had trisomy 18, and 75 had other chromosome abnormalities. The total detection rate of Down syndrome and trisomy 18 were 83.33% and 76.92%, respectively.The positive rate is lower, and the detection rate is higher in combined screening group than serum marker screening group. The median PAPPA MoM was lower and the median free β -hCG MoM and NT measured value was higher in Down syndrome pregnancies than control group. The median PAPPA and free β -hCG MoM were lower and the median NT measured value was higher in trisomy 18 pregnancies than control group.

CONCLUSIONThe first trimester prenatal screening can effectively detect Down syndrome and trisomy 18 pregnancy. The combined screening method is superior to the serum marker screening and is the preferred strategy in the first trimester prenatal screening.

Adolescent ; Adult ; Asian Continental Ancestry Group ; genetics ; Biomarkers ; blood ; China ; Chorionic Gonadotropin, beta Subunit, Human ; blood ; Chromosome Disorders ; diagnosis ; embryology ; genetics ; Chromosomes, Human, Pair 18 ; genetics ; Down Syndrome ; diagnosis ; genetics ; Female ; Fetal Diseases ; diagnosis ; ethnology ; genetics ; Genetic Testing ; methods ; Humans ; Middle Aged ; Nuchal Translucency Measurement ; Pregnancy ; Pregnancy Trimester, First ; Pregnancy-Associated Plasma Protein-A ; metabolism ; Prenatal Diagnosis ; methods ; Reproducibility of Results ; Sensitivity and Specificity ; Trisomy ; diagnosis ; genetics ; Trisomy 18 Syndrome ; Young Adult