Maternal Serum Screening Test Research Articles

The effect of a vanishing twin on first- and second-trimester maternal serum markers and ultrasound screening for aneuploidy.

A vanishing twin (VT) is the early demise of a twin fetus. It is estimated to occur in 20-30% of pregnancies associated with assisted reproductive technology. VT becomes increasingly prominent when assisted fertilization is used, because one or more embryos are transferred to the uterus. Maternal serum screening tests during pregnancy can screen for trisomy chromosomes 21, 18, and 13 and are divided into first- and second-trimester tests. In singleton pregnancies, the first trimester screening test is performed at 11-13 weeks and 6 days of gestation. It consists of two serum markers, pregnancy-associated plasma protein A and β-human chorionic gonadotropin (β-hCG), and measures nuchal translucency thickness. The second-trimester screening test was performed at 15-20 weeks and 6 days of gestation. It consists of four serum markers: alpha-fetoprotein, β-hCG, unconjugated estriol, and inhibin A. More effective screening for trisomy 21 in singleton pregnancies is achieved by analyzing cell-free DNA in the maternal blood. A VT includes a demise of the fetus. Although it affects maternal serum markers, it has not been corrected. Five studies examined the effect of VT on maternal serum markers, but the results were controversial. This study aimed to review the patterns of changes in maternal serum markers in VTs, interpret prenatal tests for pregnant women with VTs in clinical practice, and consider what information should be provided.

Prediction and Prevention of Preterm Birth: Secondary Analysis of a Randomized Intervention Trial.

Our objective was to evaluate whether pregnancy is prolonged by the use of a proteomics-based maternal serum screening test followed by treatment interventions. This is a secondary analysis of the PREVENT-PTB randomized trial comparing screening with the PreTRM test versus no screening. The primary trial analysis found no significant between-group difference in the preterm birth rate. Rather than considering a dichotomous outcome (preterm versus term), we treated gestational age at birth as a continuous variable using survival analysis. We also evaluated between-group difference in NICU length of stay and duration of respiratory support. Results indicated that pregnancy was significantly prolonged in subjects screened with the PreTRM test compared to controls (adjusted hazard ratio 0.53, 95% confidence interval 0.36-0.78, p < 0.01). Newborns of screened subjects had significantly shorter NICU stays but no significant decrease in duration of respiratory support. In the PreTRM screen-positive group, interventions that were associated with pregnancy prolongation included care management and low-dose aspirin but not 17-hydroxyprogesterone caproate. We conclude that screening with the PreTRM test followed by interventions for screen-positive pregnancies may prolong pregnancy and reduce NICU LOS, but these observations need to be confirmed by additional research.

Validation of a monoclonal unconjugated estriol antibody for use in prenatal maternal serum screening.

Unconjugated estriol (uE3) is used as a marker for fetal aneuploidy in maternal serum screening tests. The goal of this study was to examine the validity of a new immunoassay for uE3 that uses a monoclonal antibody (m-uE3) rather than the more commonly used polyclonal antibody (p-uE3). Assays were performed in the Special Chemistry laboratory at Women and Infants Hospital of Rhode Island. Residual fresh (n = 100) and frozen (n = 533) second trimester serum samples from routine clinical care were tested using p-uE3 and/or m-uE3 assays. Assay results were compared between methods using Bland-Altman plots. A median equation was developed for m-uE3 results. Down syndrome risks were compared between the two assays in a case-control sample set (21 cases each matched with five controls for the completed week of gestation, duration of freezer storage and race). Log-transformed serum uE3 levels were highly correlated between the assays (r = 0.93, p < 0.001), with the m-uE3 assay levels yielding, on average, 23% higher (standard deviation of differences in log uE3 concentrations = 0.07) results. Assay and gestation-based median equations were calculated and used to convert m-uE3 concentrations to multiples of the median (MoM). The m-uE3 MoM values fit a log Gaussian distribution well with a log standard deviation of 0.11. Down syndrome risk results were not significantly different between assays. The m-uE3 assay, with results expressed in MoMs, is suitable for screening and as a monoclonal-based assay offers the advantage of a predictable and indefinite supply of antibody to perform the assay.

Association between aberrant amino acid metabolism and nonchromosomal modifications fetal structural anomalies: A cohort study.

More than half of the cases of fetal structural anomalies have no known cause with standard investigations like karyotype testing and chromosomal microarray. The differential metabolic profiles of amniotic fluid (AF) and maternal blood may reveal valuable information about the physiological processes of fetal development, which may provide valuable biomarkers for fetal health diagnostics. This cohort study of singleton-pregnant women had indications for amniocentesis, including structural anomalies and a positive result from maternal serum screening or non-invasive prenatal testing, but did not have any positive abnormal karyotype or chromosomal microarray analysis results. A total of 1580 participants were enrolled between June 2021 and March 2022. Of the 1580 pregnant women who underwent amniocentesis, 294 were included in the analysis. There were 137 pregnant women in the discovery cohort and 157 in the validation cohort. High-coverage untargeted metabolomic analysis of AF revealed distinct metabolic signatures with 321 of the 602 metabolites measured (53%) (false discovery rate, q < 0.005), among which amino acids predominantly changed in structural anomalies. Targeted metabolomics identified glutamate and glutamine as novel predictive markers for structural anomalies, their vital role was also confirmed in the validation cohort with great predictive ability, and the area under the receiver operating characteristic curves (AUCs) were 0.862 and 0.894 respectively. And AUCs for glutamine/glutamate were 0.913 and 0.903 among the two cohorts. Our results suggested that the aberrant glutamine/glutamate metabolism in AF is associated with nonchromosomal modificantions fetal structural anomalies. Based on our findings, a novel screening method could be established for the nonchromosomal modificantions fetal structural anomalies. And the results also indicate that monitoring fetal metabolic conditions (especially glutamine and glutamine metabolism) may be helpful for antenatal diagnosis and therapy.

20-year experience on prenatal diagnosis in a reference university medical genetics center in Turkey

Background/aimAlthough cutting edge procedures such as cell-free fetal DNA isolation from maternal blood are now available, invasive prenatal tests are still being used extensively for prenatal diagnosis. The study aims to evaluate the demographic data, indications, and cytogenetic results of 9297 results of patients who underwent prenatal invasive testing for genetic analysis that were referred for the last 20 years in a University Medical Genetics Center.Materials and methodsThe records of 8363 amniocenteses, 626 chorionic villus, and 308 cordocenteses samples were retrospectively evaluated and analyzed regarding referral reasons, indications and their cytogenetic results. The total numbers and the percentages of each group were recorded; Chi-square and logistic regression analyses were performed to give the statistical likelihood of different events. ResultsThe number of referrals decreased significantly after 2009. Risk of having trisomy 21 as well as trisomy 13 and 18 significantly increased in parallel with advanced maternal age. When the 21–25 age group was compared to the older age groups in terms of having a trisomy 21 pregnancy, the risk doubled in the 36–40, 5 times higher in 41–45 and 10-fold in 46–50 age groups. No significant linear correlation between maternal serum screening test results and trisomy 21 was found, however the difference between the pregnancies whom cut-off value above and below 1/250 in maternal serum screening test were significant.ConclusionThese data have provided useful information on the frequency of referrals to the reference genetics department, and the feasibility of genetic services. By reviewing the indications and their corresponding results, we can offer invaluable insights that will be useful in genetic counseling and also in the development of more effective genetic strategies.

False-Positive Maternal Serum Screens in the Second Trimester as Markers of Placentally Mediated Complications Later in Pregnancy: A Systematic Review and Meta-Analysis.

Background Multiple-marker, maternal serum screening (MSS) has been the cornerstone of prenatal diagnosis since the 1980s. While combinations of these markers are used to predict fetal risk of Down syndrome and other genetic conditions, there is some evidence that individual markers may also predict nongenetic pregnancy complications, particularly those related to placental dysfunction. The objective of this meta-analysis was to investigate the utility of false-positive, second-trimester MSS for Down syndrome as a marker of placentally mediated complications amongst singleton pregnancies globally. Methods Electronic searches of PubMed, Medline, Embase, CINAHL, Web of Science, Scopus, and grey literature to 2019 were performed to identify observational studies comparing risk of pregnancy complications amongst pregnancies with false-positive MSS versus controls. A random-effects model of pooled odds ratios by outcome of interest (stillbirth, preeclampsia, fetal growth restriction, and preterm birth) and subgrouped by type of MSS test (double-, triple-, and quadruple-marker MSS) was used. Results 16 studies enrolling 68515 pregnancies were included. There were increased odds of preeclampsia (OR 1.28, 95% CI 1.09-1.51) and stillbirth (OR 2.46, 95% CI 1.94-3.12) amongst pregnancies with false-positive MSS. There was no significant association with preterm birth or growth restriction. Conclusions There is some evidence of an association between false-positive, second-trimester MSS for Down syndrome and increased odds of preeclampsia and stillbirth. Future large-scale prospective studies are still needed to best determine the predictive value of false-positive MSS as a marker of placentally mediated complications later in pregnancy and evaluate potential clinical interventions to reduce these risks.

Retrospective analysis of prenatal invasive diagnostic procedures in a tertiary center

Objective: This study aimed to analyze the indications and outcomes of prenatal invasive diagnostic procedures performed in a single tertiary center.&#x0D; Materials and Methods: The invasive procedure indications and karyotype results of 1666 pregnant women who underwent prenatal invasive procedures between March 2016 and November 2018 were retrospectively analyzed. The indications and results of prenatal invasive diagnostic procedures were recorded.&#x0D; Results: Amniocentesis (AS) was performed to 1060 (63.6%) patients, corion villus sampling (CVS) to 299 (17.9%), and cordocentesis (CS) to 307 (18.4%) patients. Among the prenatal invasive procedure indications, the most frequent indication was abnormal ultrasound (US) findings, with a rate of 48.3% (n= 805). A normal karyotype was detected in 85% (n= 1416) of the cases, and chromosomal abnormality was detected in 12.2% (n= 204) of the cases. Abnormal karyotype results were found in 111 (10.5%) of 1060 patients who underwent AS, 87 (29.1%) of 299 patients who underwent CVS, and 52 (16.9%) of 307 patients who underwent CS. Among the numerical chromosomal abnormalities, trisomy 21 was the most common abnormality with a rate of 46% (94/204), while inversions were the most common abnormality of structural chromosomal abnormalities at 8.8% (18/204).&#x0D; Conclusion: The results of the current study show that AS is the most common prenatal diagnostic invasive procedure. We obtained the highest fetal chromosomal anomaly rate in patients who experienced CVS. Abnormal US findings were the most common prenatal invasive diagnostic procedure indication in our study. Choosing the most appropriate invasive procedure is related to the obstetricians' experience, medical history of the patient, the gestational week at admission, maternal prenatal serum screening test results, and abnormal US findings.

Prenatal diagnosis of mosaic trisomy 2 and literature review

BackgroundWe presented two cases of mosaic trisomy 2 with high risk of maternal serum screening and non-invasive prenatal testing (NIPT). The invasive amniocentesis was performed and genetic tests including karyotype, single nucleotide polymorphism array(SNP-array), interphase fluorescence in situ hybridization (FISH) were employed to detect the chromosomal abnormality.ResultsCytogentic analysis of the case 1 and 2 showed a mosaic karyotype consisting of two cell lines (mos 47,XY,+2[8]/46,XY[19] and mos 47,XX,+2[7]/46,XX[28], respectively). SNP-array using DNA extracted from uncultured amniotic fluid cells revealed a result of arr[GRCh38](2)x2~3, which indicated that chromosome 2 may be trisomy of mosaicism in both two cases. The results of interphases FISH confirmation test showed that three red signals of the CEP 2 specific probe in 14%(14/100) and 12%(12/100) of the two cases’ cells, respectively, which indicated a mosaicism for trisomy 2 in the uncultured amniocytes. Fetal ultrasound of case 1 suggested that the long bone is smaller than the gestational age, while the case 2 showed that the biparietal diameter (BPD), head circumference (HC) and femur length (FL) were smaller than gestational age along with abnormal cardiac structure.ConclusionsWe presented two cases with mosaic trisomy 2 and performed confirmatory genetic testing using cultured and uncultured amniocytes. When maternal serum screening and NIPT suggesting high risk, genetic counselor should be alert for increasing possibility of chromosomal anomalies if combined with abnormal ultrasound findings.

Alpha feto protein in obstetrics

Alpha-feto protein in obstetricsAbstractAll obstetricians have the primary objective of obtaining an optimum obstetric and perinatal result. Diagnosis of many obstetric complications, such as restriction of intrauterine development, preeclampsia; placental necrosis or early pregnancy abruption may be conducted through several safe tests to minimize maternal and fetal morbidity or mortality. Biochemical markers were used for the earl during the 1980s and 90s .Early detection of fetal genetic disorders was performed using biochemical markers. Soon after the establishment of maternal serum screening tests for early detection of fetal abnormalities, poor pregnancy results started to be reported after unexplained isolated alpha-fetoprotein (AFP) elevation was identified. This correlation was recorded between high AFP and poor obstetric outcomes Recorded over the last 20 years. In this paper, we attempt to investigate recently updated data on the relationship between high levels of maternal serum alpha-fetoprotein (MS-AFP) with various obstetric and fetal outcomes and to assess its significance as effective markers in predicting poor outcomes for pregnanciesThe aim of the study: The aim of our study was to detect the significance of AFP in obstetric medicine.Conclusion: As a result of our research, unexplained AFP rates have been discovered with unfavorable perinatal results. Pregnancies in which AFP rates increasing rapidly were complicated with adverse perinatal outcomes in a more serious manner.

The comparison of plasma fibronectin in term and preterm delivery: A cross-sectional, descriptive-analytical study.

BackgroundPreterm delivery is one of the main causes of infant death. Therefore, prediction of preterm delivery may eliminate a large number of prenatal complications.ObjectiveThe present study aimed to understand if preterm delivery can be predicted by assessing maternal plasma fibronectin concentration.Materials and Methods Serum samples from 105 pregnant women participating in this study were collected. The plasma fibronectin were measured at 24-28 wk of gestation and again at 32-36 wk of gestation. Unfortunately, only 65 of the 105 pregnant women, returned for the second sampling. The plasma fibronectin was analyzed using ELISA method and its concentration in term and preterm deliveries was compared. The delivery dates of all the women were also recorded.ResultsOut of 105 pregnant women, 28 delivered preterm (26.7%). The Plasma fibronectin concentrations in women with preterm delivery were higher than in those who delivered at term (p = 0.001). Accordingly, Plasma fibronectin concentrations were significantly higher in the second serum samples (p = 0.01). Plasma fibronectin concentrations was also higher in obese women and in those suffering from preeclampsia (p = 0.12) and gestational diabetes (p = 0.81).ConclusionPlasma fibronectin concentrations test could be used as an optional screening test for preterm delivery at 28 to 34 wk of gestation in pregnant women who prefer to avoid vaginal sampling.

The predictive value of maternal serum screening tests for adverse pregnancy outcomes

Aim: Free beta-human chorionic gonadotropin (Fβ-hCG), pregnancy-associated plasma protein-A (PAPP-A), alpha-fetoprotein (AFP), unconjugated estriol (uE3), and inhibin-A have been shown to be useful not only in identifying chromosomal abnormalities in the first and second trimesters, but also in predicting adverse pregnancy outcomes (APOs). In this study, we aimed to investigate the predictive value of maternal serum screening tests for various APOs including preeclampsia, intrauterine growth retardation (IUGR), preterm labor, and gestational diabetes mellitus (GDM).Material and Methods: The study was carried out at our clinics and included a total of 220 pregnant women who respectively underwent the double and quadruple marker testsduring the 11th to 14th and 15th to 22nd gestational weeksbetween January 2017 and December 2018. Patient data (maternal age, parity/gravidity, gestational age, history of infertility, use of in vitro fertilization, maternal/fetal complications, preterm labor, mode of delivery, birth weight, and length of stay in the neonatal intensive care unit) were reviewed retrospectively.Results: The AFP levels were statistically significantly higher in patients with IUGR (p=0.022),GDM (p=0.036), and preterm labor (p=0.021), compared to the control group with no APO. No significant correlation was found between preeclampsia and the serum markers.Conclusion: Our results show that elevated maternal serum AFP levels might be associated with various APOs,requiring closer patient follow-up for early diagnosis and treatment.

Chromosome analysis results of first-second trimester anomaly screening tests: Single center experience

Aim: The Objective of our study was to evaluate the chromosomal analysis results that were obtained from amniocentesis, cordocentesis and chorionic villus sampling (CVS) inpatients whom had applied to the perinatology unit of Cukurova University Faculty of Medicine gynecology and obstetrics clinic with high risk in terms of chromosome anomaly according to Ultrasonography (USG).Material and Methods: Our study was conducted as a retrospective pattern. CVS, amniocentesis and cordosentesis were performed in 1298 pregnant women whom had applied to the Cukurova University Faculty of Medicine, Gynecology and Obstetrics Clinic, Perinatology Unit in the date interval between 1st December 2014-31st December 2016 with the indication of abnormal maternal serum screening tests, maternal request because of advanced maternal age, history of fetal anomaly with previous pregnancies, history of relatives with Trisomy 21, fetal abnormalities or signs of trisomy which were detected by ultrasonography and only depending on maternal request without any risk factors. Data obtained in the study were assessed using the SPSS (Statistical Package for Social Sciences) 22.0 package program. The relationships between categorical variables were determined by Chi-Square test. Relationship between normal distribution-matched, numerical data were assessed by ANOVA, Independent Sample t-test, and relationship between non-normal distributions of numerical data were assessed using Mann-Whitney U and Wilcoxon Test. Statistical significance level was determined as p 0.05.Results: Fetal anomalies were observed in 28.9% (n: 366) of the patients while 369 (28.4%) of the 1298 patients who had prenatal diagnosis had abnormalities in the maternal screening results. No chromosomal abnormalities were detected in 1120 (86.2%) of the 1298 patients who were taken into the study. 49 patients had Trisomy 21, 27 patients had Trisomy18 and 14 patients had Trisomy13. Turner syndrome was seen in 10 of thepatients. In our study, chromosomal abnormality rate of patients with more than one minor marker was found to be statistically significant (p: 0.01). Chromosomal anomaly was detected in 319 (8.4%) of 349 patients with combined test. Chromosomal anomaly was detected in 70 (19.1%) of the 366 patients who detected fetal anomaly. Chromosomal anomaly was detected in 27 (24.1%) of the 112 increased NT patients.Conclusion: In our study, 1298 invasive procedures are listed as follows; amniocentesis was performed in 841 (64.8%), cordocentesis in 57 patients (4.4%) and CVS in 400 patients (30.8%). As a result of karyotype analysis of the patients, nochromosomal anomaly was detected in 1120 patients (86.28%). In 178 patients, chromosomal anomaly (13.71%) was detected. This study aimed to determine the prevalence of fetal chromosomal anomaly in the Mediterranean region by determining the prevalence of invasive prenatal test indications and evaluating the results of invasive prenatal tests performed in our clinic in the 2-year period.

Certified Nurse-Midwives' Experiences With Provision of Prenatal Genetic Screening: A Case for Interprofessional Collaboration.

Prenatal genetic screening (GS) for the most common autosomal aneuploidies encompasses maternal serum screening (MSS) and noninvasive prenatal testing (NIPT, or cell-free fetal DNA testing). In the United States, most maternity care is provided by obstetrician-gynecologists; however, women are increasingly utilizing the services of certified nurse-midwives (CNMs). Currently, limited research exists on midwives' experiences with providing prenatal GS. Therefore, the purpose of this study was to explore CNMs' experiences in providing prenatal GS. A semistructured guide focused on MSS and NIPT was used to interview a convenience sample of 13 CNMs. Results were coded and analyzed using grounded theory to elicit overarching themes. Results were organized into 6 themes describing CNMs' prenatal GS provision: (1) clinical protocols; (2) patient education; (3) patient-CNM shared decision-making process; (4) testing initiation; (5) results delivery; and (6) follow-up coordination. Key influences on midwives' perspectives on offering prenatal GS included a noninterventionist approach to pregnancy and past experiences with false-positive MSS results. Participants had an understanding of prenatal GS that was appropriate to midwifery scope of practice. Results indicate that NIPT utilization is compatible with the midwifery philosophy of noninterventionism, although midwives had limited experiences with NIPT to date.

Identification of Edward’s Syndrome and the Importance of Maternal SerumScreening Tests

Introduction: Edwardss syndrome is a chromosomal disorder caused due to the presence of an extra chromosome 18. This syndrome was first reported in 1960 by Edward. The prevalence of this disease is approxi mately 1:6000 live births, and its prevalence increases with maternal age. Most of these fetuses die in the tenth week of pregnancy in the uterus. Case report: In this study, we presented the case of an infant with Edwards syndrome, which was diagnosed in utero. Ultrasound screening and maternal serum screening were not performed at 12 weeks. Choroid plexus cyst,atrioventricular septal defect (AVSD), and echogenicity with a diameter of 5 mm in the anterior abdominal wall were observed on ultrasound at 19 weeks. After the karyotype of amniotic fluid, Edwards syndrome was reported. According to gestational age (23 weeks) therapeutic abortion was not possible. After birth, the baby had multiple abnormalities including small oral opening, micrognathia, arch-shaped mouth, nasal bridge with an upward the tip, wide anterior fontanel, strabismus of the left eye, umbilical hernia, developmental disorders, weak cry, short neck, and closed fingers. He died at 5 months of age. Conclusion: Chromosomal abnormalities such as Downs, Edwards and Pataus syndromes are easily detectable during pregnancy and are considered for therapeutic abortion. Therefore, early diagnosis is important during pregnancy.

A retrospective exploratory study of fetal genetic invasive procedures at a University Hospital

This is a retrospective analysis of the patient demographics and cytogenetic results of patients who underwent prenatal invasive testing for genetic analysis at the Foetal Medicine Division of the Department of Obstetrics and Gynecology, Sri Ramachandra Medical College and Research Institute. The main objective of this study was to characterise the changing trends in indications of pregnant women for foetal karyotyping in a 7-year period. A total of 257 procedures were performed in this period, and there was a significant change in the trend of indications for invasive prenatal diagnosis from an advanced maternal age in 2009 to a positive screen test by 2014. Chromosome abnormalities were observed in 9.8% of the cases, with trisomy 21 being the most frequent finding. The findings demonstrate the changing trends in screening and diagnostic testing in the tertiary care centre, with an acceptance of the first and second trimester maternal serum screening tests as a determinant for high-risk pregnancies.Impact statementWhat is already known on this subject? Despite the fact that India has one of the world’s highest birth rates, there is still no public health care policy for the application of cytogenetic prenatal diagnosis. Nevertheless, we have been offering this test in our university teaching hospital since 2008, allowing us to characterise the changing trends in indications of pregnant women who sought invasive diagnostic procedures for foetal genetic studies.What do the results of this study add? The results of our study show that there were major changes in the common indications for prenatal diagnosis during the study period. In 2009, the main indication was an advanced maternal age, referred to in 31% of the cases, which declined steadily to 5% by 2014. In 2014, 51% of cases opted for a prenatal diagnosis because of a first trimester screen positive result, increasing from 12% in 2009.What are the implications of these findings for clinical practice and/or further research? This data is relevant as it would encourage other tertiary hospitals in developing countries like India to consider extending first trimester screening for all women, regardless of age and educate them on the options of prenatal genetic diagnosis for reassurance.

Interobserver reliability of sonographic fetal biometry in second trimester maternal serum screening

To examine the interobserver variability for fetal biometry parameters and to investigate whether this variability affects the second-trimester maternal serum screening test (STMSS) results. A total of 60 singleton pregnancies who were scheduled for STMSS were investigated. Two experienced sonographers performed all examinations at the same visit. The risk calclations of screening were performed according to the each operator's biometric measurements separately. Interobserver variability in measurements of fetal biometrics and the effect of this interobserver variability on the screening results were assessed. inter-observer reliability for biparietal diameter (BPD) and femur length (FL) were 0.904 and 0.888 (p < 0.00 1), respectively. interobserver reliability coefficients for trisomy 21, trisomy 13/18, and neural tube defect were 0.887, 0.999, and 0.920 (p < 0.0001), respectively. The present results demonstrate that the interobserver reliability and agreement of ultrasound measurements of fetal biometry in cases of routine prenatal screening are highly reliable.

Cytogenetic Analysis for Fetal Chromosomal Abnormalities by Amniocentesis: Review of Over 40,000 Consecutive Cases in a Single Center

Background: The aim of this study was to retrospectively investigate the 18-year experience of prenatal diagnosis of fetal karyotype analysis by amniocentesis. Methods: In this study, the authors reviewed the cytogenetic results of 40,208 fetuses with indications for amniocentesis enrolled from December 1998 to December 2015. Cytogenetic analysis of amniotic fluid was performed in all these pregnancies. Eight indications for amniocentesis were included. The detection rate and distribution of abnormal karyotypes were observed in each indication. Results: Among all these samples, abnormal maternal serum screening test was the most common indication for amniocentesis (17,536, 43.67%), followed by advanced maternal age (11,734, 29.18%), abnormal ultrasound findings (5,328, 13.25%), and required by pregnant women (2,557, 6.36%). Chromosomal abnormality was detected in 1,349 (3.36%) samples, 63.01% of the abnormalities were numerical, and 36.99% were structural. The detection rates of abnormal karyotype were 55.60% in one of the couple with chromosomal abnormality, 4.43% in the pregnant women with pathological ultrasound finding, 2.83% in the pregnant women with advanced age, and 2.73% in women with abnormal maternal serum screening tests. Of the fetuses with chromosome aberrations, 680 (50.41%) had trisomy 13, trisomy 18, or trisomy 21, and 138 (10.23%) had sex chromosome disorder. The other 531 abnormal samples included translocation, mosaicism, inversion, deletion, addition, and marker chromosome. Conclusions: Cytogenetic analysis, therefore, remained an effective approach to decrease the birth defects of fetuses with indications for amniocentesis. These results could provide meaningful suggestions for clinical genetic consulting and prenatal diagnosis.

Prenatal screening, diagnosis, and termination of pregnancy in First Nations and rural women.

The objectives of the study were to assess differences in utilization of maternal serum screening (MSS) and prenatal diagnostic testing between population subgroups and to determine the impact on chromosomal anomaly birth rates. This population-based cohort study included all female residents from Saskatchewan, Canada, who delivered a baby, experienced a fetal loss, or had a pregnancy termination between 2000 and 2005. In total, 93 171 women were included in the study dataset, with a subset (n = 35 527) evaluated to identify predictors of screening and diagnostic testing. Incidence and live birth prevalence of Down syndrome were compared across populations. MSS uptake was lower in First Nations (FN) women (9.6% vs 28.4%), and living in a rural health region moderated the difference (p < 0.001). Consequently, fewer chromosomal anomalies were prenatally diagnosed in FN women than in the rest of the population (8.3% vs 27%). Terminations of pregnancy for fetal anomaly occurred at a lower frequency amongst FN women (0.64 vs 1.34, per 1000 pregnancies), resulting in a smaller effect on Down syndrome birth rates. Utilization of MSS and diagnostic testing was lower in FN and rural populations. Further research will be necessary to understand the relevance of value preferences and access barriers. © 2016 John Wiley & Sons, Ltd.

Karyotype analysis with amniotic fluid in 12365 pregnant women with indications for genetic amniocentesis and strategies of prenatal diagnosis

We explored the strategies of prenatal diagnosis by foetal karyotype analysis in pregnant women with indications for genetic amniocentesis. Karyotype analysis of amniotic fluid was performed on 12365 pregnant women with indications for genetic amniocentesis. The detection rates and distributions of abnormal karyotypes were observed in a variety of indications for genetic amniocentesis. The detection rates of abnormal karyotype were 57.4% in either a mother or father with chromosomal abnormality, 8.5% in the pregnant women with pathological ultrasound finding (PUF), 2.79% in the pregnant women with advanced age (35 years and over) and 2.23% in the women with abnormal maternal serum screening (MSS) tests. Foetal abnormal karyotype was found in 86 pregnant women with PUF; of the 86 pregnant women, 42 had trisomy 13, 18 or 21. Of the 12365 pregnant women, foetal abnormal karyotype was found in 428 (3.46%); of the 428 foetuses, only 154 had trisomy 13, 18 or 21. In the pregnant women with abnormal MSS, 111 foetuses had abnormal karyotype, but only 36 foetuses had trisomy 13, 18 or 21. We conclude that (1) ultrasound is an important approach to prevent the birth of foetuses with chromosomal disease. (2) Non-invasive prenatal DNA detection cannot completely replace invasive prenatal diagnosis and MSS. (3) The strategies of prenatal diagnosis: Genetic amniocentesis is strongly recommended for the pregnant women with indications for genetic amniocentesis. For pregnant women who refuse invasive prenatal diagnosis, non-invasive prenatal DNA detection is first performed. If the results of non-invasive prenatal DNA detection are negative, the pregnant women are followed up by ultrasound; if the results of non-invasive prenatal DNA detection are positive, the pregnant women should undergo invasive prenatal diagnosis.

Clinical and cytogenetic results of a series of amniocentesis cases from Northeast China: a report of 2500 cases.

The aims of this study were to demonstrate the clinical and cytogenetic results of amniocentesis (AS) cases in Northeast China, to compare the incidence of different kinds of chromosomal abnormalities, and to study the association between the detection rate of chromosomal abnormalities and different indications for prenatal diagnosis. Cytogenetic analysis was performed on long-term tissue cultures of 2500 second-trimester amniotic fluid samples. The most common indication for genetic AS was abnormal maternal serum-screening test (69.56%), followed by advanced maternal age (15.04%). Chromosomal abnormality was detected in 206 (8.24%) of the 2500 samples. The detection rate of abnormal karyotypes was 62.5% in the group in which one member of the couple was a carrier of a chromosome abnormality; in the group having a positive result from noninvasive prenatal testing, the frequency was 50%. To determine the origin of fetal chromosome abnormal karyotype, 45 fetuses were analyzed. Of these, 20 were found to be de novo abnormalities and 25 were familial. The frequency and proportion of abnormal karyotypes varied substantially across different maternal AS indications. Knowing the origin and type of chromosomal abnormality would help determine termination or continuation of the pregnancy.