Quadruple Test Research Articles

Prediction of Gestational Diabetes Mellitus Risk in Early Pregnancy Using Antenatal Screening Biomarkers

Aim: In this study, we aimed to compare their success in predicting the risk of Gestational Diabetes Mellitus (GDM) using demographic (age, gravidity, parity), body mass index (BMI), first-trimester fasting blood glucose (FBG), thyroid-stimulating hormone (TSH), and antenatal screening biomarkers (dual and quadruple tests). Materials and Methods: In this study, 800 pregnant women who underwent a one-step 75 g Oral Glucose Tolerance Test (OGTT) and antenatal screening tests at a tertiary hospital between January 2017 and June 2020 were retrospectively investigated. After patients were divided into two groups based on their GDM screening test results, the examined parameters were compared between the GDM-Positive and GDM-Negative groups. Once the parameters significantly associated with GDM were determined, their clinical utility in the early diagnosis of GDM was investigated. Results: GDM was diagnosed in 159 (19.8%) of 800 patients. The GDM-Positive group had a higher age, gravidity, parity, BMI, and first-trimester serum FBG levels, as well as lower serum PAPP-A MoM levels than the GDM-Negative group (P

Quadruple Test Can Predict Hypertension in Pregnancy: The Excellent Center Hospital-based Study

Quadruple Test Can Predict Hypertension in Pregnancy: The Excellent Center Hospital-based Study

Study of special physical fitness of juniors of 17-19 years old

The article analyzes the results of special physical preparation of 17-19 years old juniors in the quadruple test uphill 300 m. The data of heart rate on the background of the physical test are disclosed. The aim of the work To determine the indicators of special preparation of 17-19 years old juniors. Result. We defined that indicator of the total time of 4 races changed by 4,9 s (t=4,13; p<0,01), by 2,1 s (t=2,42; p<0,01) of time of passing of a rise in the 1st race, by 5,6 % (t=5,46; p<0,001) of speed of passing of a rise in the 4th race concerning the first. Indicators of physical qualities of juniors of 17-19 years old during the specially-preparatory stage had a statistical difference in indicators of the Cooper's test 12-minute run (t=12,61; p<0,001), in a trunk lift in a saddle for 1 minute (t=4,99; p<0,01), whereas positive dynamics was obtained in the indicators of flexion-extension of arms in a lying down support from the floor, in a long jump from a place, in pulling up on a crossbar (p>0,05).

Role of extended first trimester screening (EFTS) in screening of aneuploidy and prediction of pre-eclampsia

: To assess the role of extended first trimester screening (EFTS) in early detection and management of preeclampsia.: A total of 501 parturients (aged 18-49 years; GA 11-13 weeks) underwent ETFS quadruple test that included age, sonographic data (CRL, Nuchal Tube (NT), ductus venosus PI) and biochemical tests (b-hCG, Alpha-fetoprotein, PLGF and PAPP-A for Trisomy 21, 18 and 13) levels. All the women were followed up for preeclampsia. Role of independent as well as combined ETFS predictors was assessed for prediction of preeclampsia employing independent samples ‘t’- and Fisher exact tests. ROC analysis was performed for continuous predictors significantly associated with preeclampsia risk. Results have been depicted in terms of sensitivity, specificity, positive and negative predictive values of different ETFS risk predictors.Meanage of women was 28.07±4.77 years. Quadruple test was negative in 422 (84.2%). It was positive for Down’s syndrome/T21 in 23 (4.6%), T21 with increased PLGF in 8 (1.6%) and increased PLGF only in 48 (9.6%) cases. A total of 14 (2.8%) women developed preeclampsia. Older age, T21 risk, PLGF risk and any quadruple test abnormality were significantly associated with preeclampsia (p<0.05). On ROC analysis, the area under the curve value of age for prediction of preeclampsia was 0.940. Among different EFTS risks, age had maximum sensitivity (100%) and specificity (88.3%). Overall quadruple test was 71.4% sensitive and 85.8% specific in prediction of preeclampsia.: EFTS was a useful strategy for reducing the burden of preeclampsia.

Predicting Adverse Pregnancy Outcomes based on Maternal Serum Markers in Quad Test

OBJECTIVE To compare adverse pregnancy outcomes (APOs) between low-risk and high-risk serum quadruple test for aneuploidy screening. METHODS This cohort design study screened pregnant women who had undergone quad test serum screening in Ratchaburi province, Thailand. The sample of 400 women was divided into two groups, low-risk quad test (n=200) and high-risk quad test (n=200) using random allocation software. Participants were followed up for final outcomes and compared for APOs. The data were analyzed using binary logistic regression analysis and risk ratios. RESULTS Of a total of 1,891 pregnant women, 206 (10.8%) had APOs. Of the women with APOs, 92 (46%) had high-risk quad test results and 32 (16%) were in the low-risk quad test group. The incidence of preeclampsia, intrauterine growth restriction (IUGR) and chromosome abnormality in the high-risk quad test group were all statistically significantly higher in the high-risk quad test group than in the low-risk quad test group (p = 0.013, 0.001, 0.043 respectively). The high-risk quad test group also had a higher incidence of preterm birth, abortion, gestational diabetic mellitus in high-risk quad test group, but the differences were non-statistically significant. CONCLUSIONS High-risk serum quad test results can help predict the risk of APOs such as preeclampsia, IUGR and chromosome abnormality. KEYWORDS quad test, maternal serum marker, adverse pregnancy outcome

Prediction of the optimal vulcanization of a fiber‐reinforced elastomeric isolator made of natural rubber‐ethylene propylene diene monomer blend

AbstractTo seismically isolate a structure, it is possible to interpose a rubber device between the foundation and superstructure that increases the period of the superstructure, a feature that allows the structure to be “transparent” to the seismic excitation. A package of several rubber pads typically constitutes a seismic isolator; they are 10–20 mm thick vertically interspersed with either steel laminas or fiber‐reinforced polymer dry textiles suitably treated. So, the rubber has a primary role and must be vulcanized correctly to create the polymer cross‐linking properly. All rubber mechanical properties are strongly affected by curing temperature and curing time. Under vulcanization is a typical production error that suppliers make in large‐scale productions, especially when the size of the devices is considerable. It is common to deal with elastomeric isolators where rubber pads have been treated at a largely suboptimal temperature. This article proposes a numerical model for predicting the cross‐linking degree of rubber pads used in seismic isolation and made by a natural rubber‐ethylene propylene diene monomer rubber compound. The aim is to correctly define the optimal curing temperature and exposition time for producing a rubber quadruple shear test specimen and a fiber reinforced elastomeric isolator (FREI). The model is a kinetic one and takes into consideration the induction time. An experimental investigation has been conducted to validate the model with visible inspections and hardness measurements taken on the rubber pads (quadruple shear specimens) and the rubber devices. The results have shown the reliability of the new numerical model proposed, with a homogeneous mechanical properties distribution obtained within the rubber pads and the FREI.

Trisomy 21 Testing in Second Trimester: Reliability Comparison of Triple and Quadruple Testing in Pakistan

Objectives: Down syndrome is a disorder that affects one in every 700 babies born, and it is one of the most frequent causes of developmental delay (DS). In Pakistan, prenatal screening for Down syndrome is not being practised according to any approved protocol. The biochemical screening that takes place during the second trimester is still carried out using the triple test. Although the quadruple test has a better sensitivity and specificity than other diagnostic methods, its usage in routine medical settings is not advised. The purpose of this study was to explore the second trimester screening for trisomy 21 (quadruple test with genetic sonogram) in order to determine its sensitivity and accuracy in comparison to biochemical testing. Place of Study: District Headquarters Hospital, Gujranwala Duration of Study: January 2021 to December 2021 Methods: This retrospective observational study was carried out in a Fetal Medicine Centre with the purpose of analysing the odds of being affected with Down syndrome, given a positive risk (OAPR) upon screening in the quadruple test; triple test and quadruple test plus a genetic sonogram for highrisk singleton pregnancies (in view of advanced maternal age; an anomaly scan showing some abnormality, etc.). Given the presence of a positive risk factor, the goal of this study was to ascertain the likelihood of having a child impacted by Down syndrome. Practical Implication: To explore the second trimester screening for trisomy 21 (quadruple test with genetic sonogram) in order to determine its sensitivity and accuracy in comparison to biochemical testing. Results: The discovery of trisomies was made after an investigation into 3,042 highrisk pregnancies with a singleton baby. 327 pregnant women who have received positive findings from a triple test, quadruple test, or quadruple test in addition to a genetic ultrasonography opt to have an amniocentesis. This decision was made after the ladies learned that their unborn child may have a genetic disorder. It was discovered that 20 of the developing babies were affected by Down syndrome. The OAPR for the quadruple test was demonstrated to be significantly higher when compared to the OAPR for the triple test (1:29.1 as compared to 1:39.2). It was found that the combination of the triple test and the genetic sonogram had the highest OAPR of 1:7. Conclusions: The triple test combined with a genetic sonogram is the most effective tool for screening for trisomy 21, and it has the potential to cut down on the number of unnecessary amniocentesis operations carried out in high-risk populations. Keywords: Down syndrome, genetic, quadruples test, second trimester screening, triple test,ultrasound

Combined maternal risk factors and the Quadruple test to predict late-onset preeclampsia in pregnant Thai women

BackgroundThis study aimed to evaluate the predictive power of a model combining maternal risk factors and the Quadruple screen test for late-onset preeclampsia (PE).MethodsAll pregnant women that received the Quadruple test for Down syndrome at 15+ 0-20+ 6 weeks’ gestation were recruited. Maternal serum α-fetoprotein, β-human chorionic gonadotropin, unconjugated estriol, and inhibin A were measured as multiples of the median. A logistic regression model was used to identify predictors associated with late-onset PE with severe features. The receiver operating characteristic (ROC) curve and area under the curve (AUC) were used to assess the model’s predictive ability.ResultsFifty-five of the 2,000 pregnant women had PE, and 31 of 55 women had late-onset PE. Multivariate analysis identified maternal age ≥ 35 years, inhibin A, history of previous PE, history of infertile, cardiac disease, chronic hypertension, and thyroid disease as significant risk factors. The area under the curve of the receiver operating characteristic curve was 0.78. The likelihood ratio to predict late-onset PE was 49.4 (total score > 60).ConclusionsOur model combining serum inhibin A with maternal risk factors was useful in predicting late-onset PE. Close monitoring of these patients is recommended.

Prenatal screening tests and prevalence of fetal aneuploidies in a tertiary hospital in Thailand.

This study evaluated prenatal screening test performance and the prevalence of common aneuploidies at Siriraj Hospital, Thailand. We collected data from screening tests which are first-trimester test, quadruple test, and noninvasive prenatal tests (NIPT) between January 2016 and December 2020. Thirty percent (7,860/25,736) of pregnancies received prenatal screening tests for aneuploidies disorders, and 17.8% underwent prenatal diagnosis tests without screening. The highest percentage of screening tests was first-trimester test (64.5%). The high-risk results were 4% for first-trimester test, 6.6% for quadruple test, and 1.3% for NIPT. The serum screening tests for trisomy 13 and 18 had no true positives; therefore, we could not calculate sensitivity. For the first-trimester test, the sensitivity for trisomy 21 was 71.4% (95% confidence intervals (CI) 30.3-94.9); specificity for trisomy 13 and 18 was 99.9% (95% CI 99.8-99.9); and for trisomy 21 was 96.1% (95% CI 95.6-96.7). For the quadruple test, the specificity for trisomy 18 was 99.6% (95% CI 98.9-99.8), while the sensitivity and specificity for trisomy 21 were 50% (95% CI 26.7-97.3) and 93.9% (95% CI 92.2-95.3), respectively. NIPT had 100% sensitivity and specificity for trisomy 13, 18 and 21, and there were neither false negatives nor false positives. For pregnant women < 35 years, the prevalence of trisomy 13, 18, and 21 per 1,000 births was 0.28 (95% CI 0.12-0.67), 0.28 (95% CI 0.12-0.67), and 0.89 (95% CI 0.54-1.45), respectively. For pregnant women ≥35 years, the prevalence of trisomy 13, 18, and 21 per 1,000 births was 0.26 (95% CI 0.06-1.03), 2.59 (95% CI 1.67-4.01), and 7.25 (95% CI 5.58-9.41), respectively. For all pregnancies, the prevalence of trisomy 13, 18, and 21 per 1,000 births was 0.27 (95% CI 0.13-0.57), 0.97 (95% CI 0.66-1.44), 2.80 (95% CI 2.22-3.52), respectively.

Evaluation of Perinatal and Neonatal Outcomes of Syrian Refugees Compared to Turkish Population: A Snapshot During the COVID-19 Pandemic.

The perinatal and neonatal outcomes of Syrian refugees during the coronavirus disease 2019 (COVID-19) pandemic are unknown. Therefore, in this study, we aimed to evaluate these outcomes. Turkish (n = 303) and Syrian refugees (n = 303) who delivered in our hospital between June 1, 2020 and December 31, 2020 were included in the study. Demographic, perinatal, and neonatal data were obtained by retrospectively evaluating hospital records. Adolescent pregnancy was more common in Syrian refugees (p < 0.001). The rates of antenatal visits, performed combined test, triple test, quadruple test, fetal anatomy ultrasound, and glucose tolerance test were lower in all refugees (p < 0.01). Furthermore, there was no difference in the mode of delivery, Hb after delivery, gestational age, birth weight, Apgar score, stillbirth, and fetal anomaly (p > 0.05 for all). Despite poorer antenatal care during the COVID-19 pandemic, Syrian refugee pregnant women had similar perinatal and neonatal outcomes compared with the Turkish pregnant population.

Assessment of indications and peri-procedural complications of amniocentesis

Aim: Assessment of indications and peri-procedural complications of amniocentesis.Materials and Methods: Cases were analyzed with some indications such as intermediate or high risk in dual and quadruple marker test, abnormal NT scan or target scan, history of child with congenital anomaly, abnormality in ultrasonography (cystic hygroma, omphalocele, diaphragmatic hernia, etc.) and to which amniocentesis will be applied. Patient and family were informed about the amniocentesis procedure, the role of this method in diagnosis and also its complications before the application. Results: The age and gestational age of the participants were 28.25±2.69 and 16.89±2.15 respectively. Most of the patients 17.14% have Hypothyroidism co morbidity. 65.71% patients show high risk assessment with dual marker & quadruple marker & abnormal NT scan & target scan indication for amniocentesis, followed by h/o child with congenital anomaly (14.2%), couple has thalassemia (11.4%), genetic disorder in family (2.9%) and chromosomal abnormality in previous child (2.9%). There was no complication of amniocentesis. Conclusion: we concluded that the genetic amniocentesis has a high success rate when performed by experienced obstetrician or foetal medicine specialist in 15-20 weeks of gestation. It should be offered to the patients when they have correct indication.

Influence of selected factors on serum AFP levels in pregnant women in terms of prenatal screening accuracy - literature review.

Alpha-fetoprotein (AFP) is one of the biochemical components of the triple (T-3) and quadruple (T-4) test used so far in prenatal screening mainly for trisomy 21 (T21) and neural tube defects (NTDs). Based on many years of experience and data collected during these studies, a variety of factors have been identified that can affect a pregnant woman's serum AFP level, and thus the risk assessment of trisomy 21 (T21) and neural tube defects. These include both unaccounted for purely medical data (e.g., from baseline information about the patient, assisted reproduction methods used, comorbidities and emerging pregnancy pathologies) and errors made during statistical analysis. Since the triple or quadruple test is usually performed between 15 and 20 weeks of pregnancy, most scientific studies are based solely on results from this period of pregnancy - limited data are available for the first and third trimesters of pregnancy. In the era of new improved screening tests, AFP has the potential to become an independent marker for pregnancy well-being evaluation.

Prediction of Low Birth Weight by Quadruple Parameters in High-Risk Pregnancies.

Aneuploidy screening is done in the early second trimester of pregnancy among all pregnant women as compulsory, with a special focus on those who had abnormal ultrasound parameters, higher dual marker risk, or other comorbidities. Recently, all individual quad markers of conventional trisomy screening have been suggested as useful in predicting adverse pregnancy outcomes (APO) such as preeclampsia, preterm labor, small for gestational age, and placental abruptions. However, similar studies on Indian pregnant women are limited. Hence, this study was intended to find the relation of quadruple markers with any other APO than aneuploidy. A retrospective study was conducted in a Tertiary Care multi-specialty hospital in North India. Data from 252 pregnant women's quadruple test was analyzed. The association of abnormal value of quadruple markers (human chorionic gonadotropin [HCG]/alpha-fetoprotein/uE3/Inhibin A) with adverse outcomes was evaluated. Multiple logistic regression analysis and classification and regression tree were used to predict the significant risk factor in high-risk pregnancies. In the study, a total (n = 252) of pregnant women, 190 were screened as high-risk pregnancies, whereas the remaining 62 were reported as low-risk using trisomy screening in the quadruple test. Baby birth weight was observed to be significantly associated with Inhibin-A, and HCG (P < 0.001), whereas Corrected (Corr)-multiple of median (MoM)-HCG (>1.415) and Inhibin-A Corr-MoM (>364.175) were the suitable predictor for the LBW. Both parameters were significantly higher in the high-risk group as compared to the low-risk group (each P < 0.05). Abnormal deviation of biochemical markers from aneuploidy screening assessment could help predict other perinatal adverse outcomes such as low birth weight babies.

Quantification of serum homoarginine, methylated arginine and inhibin-A levels in a high-risk pregnancy

The plasma levels of homoarginine (h-Arg) and methylated arginine have proven to be an independent cardiovascular risk factor. We aimed to determine the h-Arg and methyl arginine levels in serums of high-risk pregnancy causing potential complications. These participants were divided into four groups as the control group with quadruple test, the high-risk group quadruple test the control group with binary test, the high-risk group with quadruple test that have a positive result from second-trimester screening with a cut-off value of 1 in 300. The serum methyl arginine and homoarginine levels were analysed with liquid chromatography-tandem mass spectrometry. Serum h-Arg levels were found to be higher in high-risk groups compared to control groups and it was also detected higher in the groups with quadruple test than the groups with binary test (p < .05). H-Arg levels in the groups showed strong negative correlation with age and serum inhibin-A levels (r = −0.288, p < .001). Also, there was a strong negative correlation between serum asymmetric dimethylarginine (ADMA) and serum inhibin-A levels (r = −0.352, p < .001). H-Arg may be a new risk marker to detect high-risk pregnancies in early pregnancy. In addition to, methylated arginine such as ADMA has a key regulator in a physiological concentration of h-Arg. IMPACT STATEMENT What is already known on this subject? H-Arg levels decrease may be associated with preeclampsia, GDM, macrosomia, low birth weight, and preterm delivery in pregnancy. What do the results of this study add? Serum h-Arg levels were found to be higher in high-risk groups. Additionally, h-Arg levels and ADAM, one of the methylated arginines in the groups showed a strong negative correlation with serum inhibin-A levels What are the implications of these findings for clinical practice and/or further research? H-Arg may be a new risk marker to detect high-risk pregnancies

Biochemical Serum Markers Influencing Maternal Age Risk for Down's Syndrome in Quadruple Marker.

Objective: Maternal age is the primary risk factor associated with Down syndrome (DS) in the fetus. Biochemical serum markers in maternal screenings have improved DS detection rates in prenatal screenings. However, there is a dilemma regarding which age group should undergo preliminary noninvasive screening before undergoing invasive diagnostic procedures. Based on recommendations, all pregnancies are at risk of chromosomal abnormalities. While all women should be offered screenings, those over 35 are mainly offered an invasive diagnostic procedure, and serum screening tests are of little benefit for this age group. This study evaluated the maternal serum screening population and the significance of the final screen positivity rate in the risk group aged above 35 years.Method: An observational retrospective study was conducted on a cohort of pregnancies in the second trimester (14-20 weeks and 6 days of gestation) over a period of one year. The quadruple test consisted of serum alpha-fetoprotein (AFP), free beta hCG, unconjugated estriol e3 (Ue3), and inhibin-A. The risk for DS was calculated using software with corrections for ethnicity, smoking, weight, and age. We compared the age risk for DS with the biochemical risk. Statistical analysis was done using McNemar’s test to test the proportion of screen-positive (SP) cases between the two calculation methods, i.e., age alone versus final risk calculation with biomarkers.Results: The proportion of SP cases from age risk and final risk were 56.3% and 12.6%, respectively. The computed McNemar’s chi-square test statistic was 97.959 (p < 0.001), which showed a significant reduction in SP cases when biomarkers were added to screen for trisomy 21 women aged >35 years.Conclusion: The age risk of DS increased with increasing maternal age. Notably, the final biochemical risk in this population was significantly lower. Consequently, we proposed that a noninvasive serum screening be used to screen all age groups to rule out negative screen cases before subjecting them to invasive procedures.

Investigation of the Number of Tests Required for Assaying Plasma Biomarkers Associated with Alzheimer's Disease Using Immunomagnetic Reduction.

IntroductionConcentrations of plasma biomarkers associated with Alzheimer’s disease have been reported to be as low as several tens of picograms/milliliter (pg/ml). However, in assays measuring these biomarkers, it is likely that repeated measurements are necessary to obtain reliable values.MethodsWe performed assays as a single test or as duplicate, quadruplicate, fivefold and tenfold repeated tests, on samples spiked with different concentrations of amyloid β 1–40 (Aβ1–40; 1–1000 pg/ml), Aβ1–42 (1–30,000 pg/ml) and total Tau protein (T-Tau; 0.1–1000 pg/ml), with the aim to to calculate the coefficients of variation (CVs).ResultsThe results demonstrated common changes in the CVs with changes in the number of tests for a given sample: the CVs decreased with increases in the number of tests from one to ten. All CV values were distributed within the range of 0.35 to 15.5%; as such, the CV values were all lower than the acceptable value of 20%.ConclusionBased on this study, a single assay of Aβ1–40, Aβ1–42 and T-Tau, respectively, provides reliable results in terms of the measurement of that plasma biomarker.

Ethnicity-Specific Normative Models of Quadruple Test as a Screening Test for Down Syndrome.

Background and Objectives: To establish normative models for median levels of serum biomarkers of the second trimester quad test (alpha-fetoprotein: AFP; free beta-human gonadotropins: hCG; inhibin-A; and unconjugated estriol: uE3) specific to Thai women and to compare multiples of the median (MoMs) derived from ethnicity-specific models and those derived from Caucasian models with ethnic correction. Materials and Methods: A cross-sectional study was undertaken in a tertiary, medical teaching center among low-risk pregnant Thai women between 14 and 21 weeks of gestation to measure the levels of the four serum biomarkers. The measured values of each biomarker were analyzed using the multivariable factorial polynomial technique for quantile regression as a function of gestational age and maternal weight. Results: The Thai-specific normative models for the four biomarkers were generated and available for use. The MoMs of all individuals generated from our models were significantly different from conventional (Caucasian) models with ethnic correction (Wilcoxon signed-rank test; p < 0.0001 for all biomarkers). The MoMs of AFP and hCG from both methods were in agreement, but those from Thai-specific models were significantly higher. However, those of inhibin-A and uE3 were markedly different and ethnic correction was unlikely to be useful. Conclusions: The Thai-specific normative models of the quad test as a function of gestational age and maternal weight were constructed using multivariable factorial polynomial models, better than simple quantile regression or log-linear regression used in earlier decades. The analysis of MoMs supports the use of ethnicity-specific models instead of Caucasian models with ethnic correction.

Ethnic-specific reference range affects the efficacy of quadruple test as a universal screening for Down syndrome in a developing country.

ObjectiveTo evaluate the efficacy of the quadruple test for potential use as a Thai national policy for Down syndrome (DS) screening and establish an accurate equation for risk estimation of Down syndrome based on gestational age, weight and the ethnic-specific reference range of our population.MethodsA prospective study was conducted on singleton pregnancies at 14 to 21 weeks of gestation to evaluate the efficacy of quadruple DS screening using the automatically calculated Western European descent factor (WF) in our population and the impact of screening using a specific Thai ethnic factor as well as to establish an equation for the risk estimation of DS based on gestational age, weight and a local Thai ethnic factor to correct for the impact of ethnic factor on the screening efficacy.ResultsOf a total of 5,515 women, 12 cases of DS and 8 cases of other aneuploidies were found. The detection rate, false positive rate and specificity were 75.0%, 9.1% and 90.9%, respectively, by automatic calculation with the widely used WF; the screening efficacy was lower when used in Asian populations than in other studies. The best-fitted regression equation of serum quadruple screening of AFP, free β-hCG, uE3 and inhibin A was established by adjustment for gestational age (GA) in days, maternal weight and our Thai-specific ethnic reference range which was created for this study. Calculations with our Thai-specific ethnic model gave a better detection rate of 83.3%, a false positive rate of 9.6% and specificity of 90.4%.ConclusionThe serum quadruple test had a lower detection rate than expected when the risk estimation was based on the WF reference range. The serum quadruple test using WF had significantly different levels when corrected with our ethnic-specific factor. Using our local ethnic specific model could increase the detection rate of DS screening in Thailand with a minimal increase in false positive rates. Our findings indicate that DS screening should be adjusted with an appropriate individual ethnic factor when used for national screening.

Evaluation of Amniocentesis Results in Patients With High-Risk Cell-Free Fetal DNA

Objectives: The present research was conducted to evaluate the accuracy of cell-free fetal DNA (cffDNA) in diagnosing chromosomal abnormalities and measure consistency in diagnostic results between this assay and amniocentesis. Materials and Methods: This retrospective observational study recruited pregnant women presenting for Down’s syndrome screening. These women underwent the nuchal translucency ultrasound and their serum levels of pregnancy-associated plasma protein A and free beta-human chorionic gonadotropin were measured based on the aim of the study. Amniocentesis was administered in subjects with high or uncertain risk for fetal chromosomal abnormalities and cffDNA testing or the quadruple screen test in those with moderate risk. The women diagnosed as high-risk cases in cffDNA testing also underwent amniocentesis to confirm their diagnosis. Results: Amniocentesis showed trisomy 21 as the most prevalent chromosomal abnormality in 66 (67.3%) cases, followed by trisomy 18 in 12 (12.2%) and trisomy 13 in 7 (7.1%). False-positive cffDNA results were obtained in 8 (8.2%) cases. The coefficient of agreement between these two tests was, however, obtained as 0.845 (P&lt;0.0001), and their results were significantly correlated with each other (χ2=369, P&lt;0.0001). Moreover, cffDNA was found to diagnose prenatal chromosomal abnormalities with a sensitivity of 100%, a specificity of 50%, a positive predictive value of 91.8%, and a negative predictive value of 100%. Conclusions: Given the high sensitivity of cffDNA observed in diagnosing chromosomal abnormalities, this assay can play a key role as a non-invasive procedure in prenatal diagnoses.

Performance of second-trimester maternal biochemistry screening (quadruple test vs. triple test) for trisomy 21: An Indian experience.

Background & objectives:Down syndrome (DS) is one of the most common causes of developmental delay. In India, there is no protocol for prenatal screening of DS. Second-trimester biochemical screening is still being done by triple test. Quadruple test is with better sensitivity and specificity but is not advised routinely. So, the objective of this study was to evaluate the sensitivity and accuracy of the second-trimester screening (quadruple test with genetic sonogram) for trisomy 21 as compared to biochemical testing.Methods:This retrospective observational study was carried out in a Fetal Medicine Centre to analyze the odds of being affected with DS, given a positive risk (OAPR) upon screening in the quadruple test; triple test and quadruple test plus a genetic sonogram for high-risk singleton pregnancies (in view of advanced maternal age; an anomaly scan showing some abnormality, etc).Results:3175 high-risk singleton pregnancies were screened for trisomy 21. 394 women underwent amniocentesis on the basis of triple test, quadruple test or quadruple plus genetic sonogram positive. 17 foetuses were diagnosed to have DS. The quadruple test was found to have a higher OAPR as compared to the triple test (1:30.1 as compared to 1: 40.2). Quadruple test plus the genetic sonogram was found to have the highest OAPR of 1:6.Interpretation & conclusions:Best screening for trisomy 21 is provided with quadruple test with genetic sonogram which can lower the rates of unnecessary amniocentesis in high-risk population.