BACKGROUND

Down syndrome or trisomy 21, the most common chromosomal disorder, results from the presence of a third copy of chromosome 21 and manifests as mild to moderate intellectual disability, growth retardation, congenital heart defects, gastrointestinal abnormalities, and characteristic facial features. Several methods have been used to screen for Down syndrome in the prenatal period, such as ultrasound, biomarkers, cell-free DNA testing, and combinations of these tests. A positive result from one or more of these screening tests signals the need for confirmatory karyotyping to clinch the diagnosis. Ultrasound between 11 to 14 weeks of gestation can evaluate nuchal translucency (NT) to screen for Down syndrome. During the second trimester, a triple or quadruple test can also be performed alone or in addition to NT to quantify Down syndrome risk. In limited resource settings however, only the measurement of NT via ultrasound can be performed since biomarker tests are either unavailable or inaccessible. While the diagnostic performance of NT measurement alone has been investigated in several observational studies, there is no consensus on its performance as a sole test to screen for Down syndrome.

To determine the diagnostic performance of NT during prenatal first-trimester ultrasound as a screening test for Down syndrome.

We performed a systematic search on the PubMed, ProQuest, and Cochrane Library databases for recent systematic reviews and meta-analyses that addressed the objective. The existing reviews found were then independently appraised by the two reviewers with the AMSTAR-2 checklist. To update the existing reviews, a systematic search was done in the same databases to identify additional primary diagnostic studies, which were appraised using the QUADAS-2 tool. Random-effects univariate meta-analysis and summary receiving operator curve (HSROC) analysis for the outcomes were performed using Review Manager version 5.4 and R version 4.2.2, respectively. Subgroup analysis was performed by stratifying the baseline risk of mothers for fetal anomaly as low- or high-risk. Highrisk mothers were defined as women with risk factors such as advanced age, positive serum screen, presence of other ultrasound anomalies, and history of previous fetus with anomaly.

We found 22 cohort studies (n=225,846) of women at low-risk for fetal anomaly. The pooled sensitivity was 67.8% (95% CI: 61.4%-73.6%, I2=70.4%) and specificity was 96.3% (95% CI: 95.5%-96.9%, I2=96.7%). For low-risk women, the overall certainty of evidence was low, due to different modes of verification and heterogeneity not completely explained by variability in baseline risk or cut-points. Seven studies (n=9,197) were on high-risk women. The pooled sensitivity was 62.2% (95% CI: 54.1%-69.7%, I2=38.8%) and specificity was 96.5% (95% CI: 93.6%-98.1%, I2=95.5%). For women at high-risk, the evidence was rated as moderate due to differential verification.

Our analysis showed that NT measured through first-trimester ultrasound is specific for Down syndrome but has low sensitivity. Despite this, it is a useful screening test for Down syndrome in low-resource settings where other strategies may not be available or accessible. Furthermore, interpretation of NT results must take into consideration its limited sensitivity as this may lead to missed cases.

BACKGROUND

Down syndrome or trisomy 21, the most common chromosomal disorder, results from the presence of a third copy of chromosome 21 and manifests as mild to moderate intellectual disability, growth retardation, congenital heart defects, gastrointestinal abnormalities, and characteristic facial features. Several methods have been used to screen for Down syndrome in the prenatal period, such as ultrasound, biomarkers, cell-free DNA testing, and combinations of these tests. A positive result from one or more of these screening tests signals the need for confirmatory karyotyping to clinch the diagnosis. Ultrasound between 11 to 14 weeks of gestation can evaluate nuchal translucency (NT) to screen for Down syndrome. During the second trimester, a triple or quadruple test can also be performed alone or in addition to NT to quantify Down syndrome risk. In limited resource settings however, only the measurement of NT via ultrasound can be performed since biomarker tests are either unavailable or inaccessible. While the diagnostic performance of NT measurement alone has been investigated in several observational studies, there is no consensus on its performance as a sole test to screen for Down syndrome.

To determine the diagnostic performance of NT during prenatal first-trimester ultrasound as a screening test for Down syndrome.

We performed a systematic search on the PubMed, ProQuest, and Cochrane Library databases for recent systematic reviews and meta-analyses that addressed the objective. The existing reviews found were then independently appraised by the two reviewers with the AMSTAR-2 checklist. To update the existing reviews, a systematic search was done in the same databases to identify additional primary diagnostic studies, which were appraised using the QUADAS-2 tool. Random-effects univariate meta-analysis and summary receiving operator curve (HSROC) analysis for the outcomes were performed using Review Manager version 5.4 and R version 4.2.2, respectively. Subgroup analysis was performed by stratifying the baseline risk of mothers for fetal anomaly as low- or high-risk. Highrisk mothers were defined as women with risk factors such as advanced age, positive serum screen, presence of other ultrasound anomalies, and history of previous fetus with anomaly.

We found 22 cohort studies (n=225,846) of women at low-risk for fetal anomaly. The pooled sensitivity was 67.8% (95% CI: 61.4%-73.6%, I2=70.4%) and specificity was 96.3% (95% CI: 95.5%-96.9%, I2=96.7%). For low-risk women, the overall certainty of evidence was low, due to different modes of verification and heterogeneity not completely explained by variability in baseline risk or cut-points. Seven studies (n=9,197) were on high-risk women. The pooled sensitivity was 62.2% (95% CI: 54.1%-69.7%, I2=38.8%) and specificity was 96.5% (95% CI: 93.6%-98.1%, I2=95.5%). For women at high-risk, the evidence was rated as moderate due to differential verification.

Our analysis showed that NT measured through first-trimester ultrasound is specific for Down syndrome but has low sensitivity. Despite this, it is a useful screening test for Down syndrome in low-resource settings where other strategies may not be available or accessible. Furthermore, interpretation of NT results must take into consideration its limited sensitivity as this may lead to missed cases.

Human ; Mass Screening ; Mothers ; Nuchal Translucency Measurement ; Prenatal Diagnosis

OBJECTIVES: The diagnostic value of ultrasonographic quantitative indicators of umbilical cord coiling, such as the umbilical coiling index (UCI) and pitch value, in identifying hypercoiling and predicting adverse pregnancy outcomes remains controversial. This study aims to evaluate the predictive value of UCI, pitch value, and the cerebroplacental ratio in pregnancies complicated by umbilical cord hypercoiling. METHODS: Pregnant women with densely coiled umbilical cords identified by routine obstetric ultrasound at Changsha Maternal and Child Health Hospital between November 2022 and November 2024 were enrolled. Complete clinical data, including UCI, pitch value, and cerebroplacental ratio (CPR), were collected. Pregnancy outcome scores were calculated, and newborns were categorized into the normal outcome group (n=177) and adverse outcome group (n=85), with the latter further subdivided into mild (n=51), moderate (n=19), and severe (n=15) subgroups. Differences in baseline data, UCI, pitch value, and incidence of CRP<1 were compared between groups and among subgroups. Correlations between UCI, pitch value, and adverse pregnancy outcomes were analyzed. Receiver operating characteristic (ROC) curve were used to assess the predictive performance of UCI, pitch value, CPR<1, and their combinations. RESULTS: Compared with the normal outcome group, the adverse outcome group had higher age, parity, parity, incidence of CPR<1, and UCI, while gestational age at delivery and pitch values were lower (all P<0.05). The incidence of obesity, gestational diabetes mellitus, and hypertensive disorders of pregnancy did not differ significantly between the 2 groups (all P>0.05). The normal outcome group showed lower UCI and higher pitch values than all 3 adverse outcome subgroups (all P<0.05), while differences among the 3 adverse subgroups were not significant (all P>0.05). UCI was positively correlated with adverse pregnancy outcomes (r_s=0.350, P<0.05), whereas pitch value was negatively correlated (r_s=-0.286, P<0.05). ROC curve analysis showed that the area under the curve (AUC) values for predicting adverse outcomes were 0.837 for UCI, 0.886 for pitch value, and 0.610 for CPR<1, with sensitivities of 77.6%, 82.4%, and 27.1% and specificities of 78.5%, 83.6%, and 94.9%, respectively. The combined UCI+CPR<1 and pitch value+CPR<1 models yielded AUCs of 0.841 and 0.886, with sensitivities of 78.8% and 81.2% and specificities of 78.5% and 84.2%, respectively. No significant differences were found between the AUCs of UCI and pitch value (P>0.05), but both outperformed CPR<1 alone (both P<0.001). The combined models showed no significant improvement over UCI or pitch value alone (both P>0.05), though both were superior to CPR<1 alone (both P<0.001). CONCLUSIONS Most umbilical cord hypercoiling cases had favorable outcomes, with UCI, pitch value, CPR<1 and their combinations demonstrating significant predictive value for adverse pregnancy outcomes.
Humans ; Female ; Pregnancy ; Pregnancy Outcome ; Adult ; Ultrasonography, Prenatal/methods* ; Umbilical Cord/diagnostic imaging* ; Hemodynamics ; Predictive Value of Tests ; Infant, Newborn ; ROC Curve

OBJECTIVES: To construct an intelligent analysis model for classifying fetal orientation during intrapartum ultrasound videos based on multi-feature fusion. METHODS: The proposed model consists of the Input, Backbone Network and Classification Head modules. The Input module carries out data augmentation to improve the sample quality and generalization ability of the model. The Backbone Network was responsible for feature extraction based on Yolov8 combined with CBAM, ECA, PSA attention mechanism and AIFI feature interaction module. The Classification Head consists of a convolutional layer and a softmax function to output the final probability value of each class. The images of the key structures (the eyes, face, head, thalamus, and spine) were annotated with frames by physicians for model training to improve the classification accuracy of the anterior occipital, posterior occipital, and transverse occipital orientations. RESULTS: The experimental results showed that the proposed model had excellent performance in the tire orientation classification task with the classification accuracy reaching 0.984, an area under the PR curve (average accuracy) of 0.993, and area under the ROC curve of 0.984, and a kappa consistency test score of 0.974. The prediction results by the deep learning model were highly consistent with the actual classification results. CONCLUSIONS The multi-feature fusion model proposed in this study can efficiently and accurately classify fetal orientation in intrapartum ultrasound videos.
Humans ; Female ; Ultrasonography, Prenatal/methods* ; Pregnancy ; Fetus/diagnostic imaging* ; Neural Networks, Computer ; Video Recording

Humans ; Pulmonary Atresia/therapy* ; Pregnancy ; Female ; China ; Consensus ; Fetal Heart ; Ultrasonography, Prenatal ; Heart Defects, Congenital/therapy* ; Ventricular Septum ; Cardiac Surgical Procedures/methods*

Pregnancy ; Female ; Humans ; Turner Syndrome/diagnostic imaging* ; Pregnancy Trimester, First ; Pregnancy Trimester, Second ; Ultrasonography, Prenatal ; Risk Factors

Humans ; Pregnancy ; Female ; Umbilical Cord/diagnostic imaging* ; Pregnancy Outcome ; Ultrasonography ; Ultrasonography, Prenatal

OBJECTIVE: To investigate the association of isolated thyroid peroxidase antibody (TPOAb) positive in the first trimester with fetal growth. METHODS: A total of 16 446 pregnant women were included in the birth cohort study, whose last menstrual period was between May 2016 and April 2019 and with singleton pregnancy. Maternal serum samples were collected when they firstly came for prenatal care in the first trimester. The pregnant women were consecutively seen and followed in the hospital and the information of pregnant women was extracted from the electronic medical information system. The pregnant women were divided into isolated TPOAb positive group (n=1 654) and euthyroid group (n=14 792). Three fetal ultrasound examinations were scheduled during the routine prenatal visits at the hospital and were performed by trained sonographers. All fetal growth indicators were quantified as gestational age- and gender- adjusted standard deviation score (Z-score) using the generalized additive models for location, scale and shape (GAMLSS). Fetal growth indicators included estimated fetal weight (EFW), abdominal circumference (AC), biparietal diameter (BPD), femur length (FL) and head circumference (HC). Fetal growth restriction (FGR) was defined as AC or EFW Z-score＜3rd centile based on clinical consensus. Generalized estimating equation (GEE) analysis was applied to assess the association of maternal isolated TPOAb positive with fetal growth. The generalized linear model was further used to analyze the association between isolated TPOAb positive and fetal growth indicator at different gestational ages when the fetal growth indicator was significantly associated with isolated TPOAb positive in the GEE mo-del. RESULTS: The median gestational age at three ultrasound measurements was 23.6 (23.3, 24.1), 30.3 (29.7, 30.9), 37.3 (37.0, 37.7) weeks, respectively. The BPD Z-score was higher in isolated TPOAb positive women, compared with the euthyroid pregnant women after adjustment (β=0.057, 95%CI: 0.014-0.100, P=0.009). The generalized linear model showed the BPD Z-score was higher in the isolated TPOAb positive women at the end of 21-25 weeks (β=0.052, 95%CI: 0.001-0.103, P=0.044), 29-32 weeks (β=0.055, 95%CI: 0.004-0.107, P=0.035) and 36-40 weeks (β=0.068, 95%CI: 0.011-0.125, P=0.020), compared with the euthyroid pregnant women. There was no difference in other fetal growth indicators (EFW, AC, FL and HC) and FGR between the isolated TPOAb positive and euthyroid pregnant women. CONCLUSION The BPD Z-score was slightly increased in the isolated TPOAb positive pregnant women in the first trimester, while other fetal growth indicators were not changed. The reproducibility and practical significance of this result need to be confirmed.
Pregnancy ; Female ; Humans ; Pregnancy Trimester, First ; Iodide Peroxidase ; Cohort Studies ; Reproducibility of Results ; Fetal Development ; Fetal Weight ; Fetal Growth Retardation ; Ultrasonography, Prenatal

OBJECTIVE: To explore the genetic basis for a fetus with multiple malformations. METHODS: Clinical data of the fetus was collected, Amniotic fluid sample of the fetus was subjected to conventional G-banded karyotyping, low-depth whole genome copy number variants detection and whole exome sequencing (WES). Candidate variant was verified by Sanger sequencing of the fetus and its parents. RESULTS: Prenatal ultrasound scan at 21⁺⁵ gestational weeks had revealed increased nuchal thickness (9.0 mm), enhanced echos of bilateral renal parenchyma, seroperitoneum, left pleural effusion and right displacement of the heart. The mother had a previous history of terminated pregnancy for multiple fetal anomalies. No abnormality was found by conventional karyotyping and CNV analysis, though WES revealed that the fetus has harbored a de novo heterozygous c.607C>T (p.Arg203Trp) variant of the ACS1 gene (NM_018026.3), and the result was validated by Sanger sequencing. CONCLUSION Through WES and prenatal ultrasonography, the fetus was diagnosed with Schuurs-Hoeijmakers syndrome due to the heterozygous c.607C>T (p.Arg203Trp) variant of the PACS1 gene (NM_018026.3). For fetuses with multiple malformations, WES can help to reveal the genetic etiology when CNV result is negative.
Female ; Pregnancy ; Humans ; Prenatal Diagnosis ; Ultrasonography, Prenatal ; Syndrome ; Fetus ; Abnormalities, Multiple ; Vesicular Transport Proteins