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Communicating the diagnosis of Down Syndrome to a couple of parents is never easy, whether before or after birth. As doctors, we must certainly rely on our own relational skills, but it is also necessary to be confident in some general indications, which are often overlooked in the strict hospital routine. This article is intended as a summary of the main articles published on this subject in the international literature, collecting and summarising the most important indications that have emerged in years of medical practice all over the world as well as in our personal experience. The diffusion of these guidelines is essential to help the doctor in this difficult task, on which there is often little training, and above all to guarantee to the parents the least traumatic communication possible. [ABSTRACT FROM AUTHOR]

Objective: To compile current usage of serum-based prenatal screening for Down syndrome in the United States and compare it with results from a similar 2011/2012 survey. Setting: The College of American Pathologists maternal screening proficiency testing survey includes a supplemental question on the first of three yearly distributions. Methods: Information regarding tests offered and the monthly number of pregnancies tested for US-based laboratories were reviewed. Results were stratified by size of laboratory, tests offered, and pregnancies tested. Findings were compared to an earlier survey. Results: Fifty-six laboratories reported they will have screened 1,131,336 pregnancies in 2020. Of these, 36% are screened by stand-alone first trimester testing, 48% by stand-alone second trimester testing, and 16% using tests that integrate results from both trimesters. Eighty percent of all serum screens were provided by the five laboratories that performed the most screens (at least 50,000). These five performed similar proportions of first or second trimester screens (42.2% and 41.8%, respectively). Compared to eight years earlier, there are now 54% fewer laboratories. Pregnancies screened using the first trimester, second trimester, and integrated protocols were lower by 27%, 69%, and 72%, respectively. The serum screening activity in the US showed a 62% decrease from 2012 levels. During 2012–2020, the number of cell-free DNA tests increased from negligible to 1,492,332. Conclusions: Maternal serum screening for common aneuploidies has changed significantly in eight years with fewer laboratories, a shift toward larger laboratories and a 2.5-fold reduction in pregnancies tested, likely due to the introduction of cell-free DNA screening. [ABSTRACT FROM AUTHOR]

Background: The purpose of the study was to evaluate the use of contingent prenatal screening for the detection of Down's syndrome and neural tube defects (NTDs) in west of Iran. Methods: A prospective study was conducted on 653 pregnant women referred to a medical diagnostic laboratory (Imam Reza Clinic, Kermanshah, Iran) for contingent prenatal screening tests between October 2016 to September 2017. Results: Among 651 women screened in the first trimester, 8 (1.22%) pregnancies were screen-positive for Down's syndrome. In the second trimester, among 605 women, 25 (4.13%) had a positive result and all of these women voluntarily underwent amniocentesis. Overall, five pregnancies were complicated with chromosomal abnormalities, including five cases of Down's syndrome. Conclusion: In a nutshell, the contingent prenatal screening tests were found to be useful for estimation of Down's syndrome as well as NTDs in both young and older mothers in west of Iran. These tests should be performed for pregnant women before an invasive test for Down's syndrome. [ABSTRACT FROM AUTHOR]

Background: Quantitative fluorescence-polymerase chain reaction (QF-PCR) is an inexpensive and accurate method for the prenatal diagnosis of aneuploidies that applies short tandem repeats (STRs) as a chromosome-specific marker. Despite its apparent advantages, QF-PCR is not applicable in all cases due to the presence of uninformative STRs. This study was carried out to investigate the efficiency of a method based on applying segmental duplications (SDs) in conjunction with STRs as an alternative to stand-alone STR-based QF-PCR for the diagnosis of Down syndrome. Methods: Fifty amniotic fluid samples from pregnant women carrying Down syndrome fetuses, 9 amniotic fluid samples with 1 or without any informative STR marker (inconclusive), and 100 normal samples were selected from Shiraz, Iran, between October 2015 and December 2016. Analysis was done using an in-house STR-SD-based multiplex QF-PCR and the results were compared. Statistical analysis was performed using MedCalc, version 14. Results: All the normal, Down syndrome, and inconclusive samples were accurately identified by the STR-SD-based multiplex QF-PCR, yielding 100% sensitivity and 100% specificity. Karyotype analysis confirmed all the cases with normal or trisomic results. Conclusion: The STR-SD-based multiplex QF-PCR correctly identified all the normal and trisomy 21 samples regardless of the absence of informative STR markers. The STR-SD-based multiplex QF-PCR is a feasible and particularly useful assay in populations with a high prevalence of homozygote STR markers. [ABSTRACT FROM AUTHOR]

Objective: To report on the routine clinical implementation of cell-free DNA (cfDNA) analysis of maternal blood for trisomies 21, 18 and 13, contingent on the results of the first-trimester combined test in twin pregnancy.Methods: Screening for trisomies 21, 18 and 13 was carried out in 959 twin pregnancies by assessment of a combination of maternal age, fetal nuchal translucency thickness, and serum free β-human chorionic gonadotropin and pregnancy-associated plasma protein-A at 11-13 weeks' gestation in two UK NHS hospitals. Women in the high-risk group (risk ≥ 1 in 100) were offered the option of invasive testing, cfDNA testing or no further testing, and those in the intermediate-risk group (risk 1 in 101 to 1 in 2500 in the first phase of the study and 1 in 101 to 1 in 500 in the second phase) were offered cfDNA or no further testing. The trisomic status of the pregnancies was determined by prenatal or postnatal karyotyping or examination of the neonates.Results: In 42 (4.4%) of the 959 pregnancies, there was termination, miscarriage or stillbirth with no known karyotype or there was loss to follow-up. The 917 pregnancies with known trisomic status of both twins included six that were discordant for trisomy 21, four that were discordant for trisomy 18 and 907 with no trisomy 21, 18 or 13. Following combined screening, 47 (5.1%), 203 (22.1%) and 667 (72.7%) of the pregnancies were classified as high risk, intermediate risk and low risk, respectively. The high-risk group included five (83.3%) cases of trisomy 21 and three (75.0%) of trisomy 18. The cfDNA test was carried out in 224 pregnancies and results were provided in 214 (95.5%); this group included six pregnancies with trisomy 21, three with trisomy 18 and 206 with no trisomy 21, 18 or 13. The cfDNA test classified correctly as screen positive all six cases of trisomy 21 and two of the three with trisomy 18, and as screen negative for each of the trisomies all 206 unaffected pregnancies. Contingent screening led to prenatal detection of all cases of trisomy 21 and three of four with trisomy 18.Conclusion: This study has demonstrated the feasibility of introducing cfDNA testing, contingent on the results of the first-trimester combined test for major trisomies, in a routine population of twin pregnancies. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Dual detection of α-fetoprotein (AFP) and free β-human chorionic gonadotropin (β-HCG) is a common screening method for Down syndrome in the second trimester and its efficacy is assessed by false-positive rate (FPR). The present study aimed to investigate the effects of the bias in median multiple of the median (mMoM) values of AFP and free β-HCG on FPR. The bias in mMoM values of AFP and free β-HCG and the bias in mMoM values under different gestational ages and weight groups were analyzed. Median equations were adjusted, and medians in LifeCycle software were replaced by local medians. Following two adjustments of the median equations, all indices including FPR, mMoM values of markers and mMoM values under different gestational ages and weight groups generally reached an ideal state. In conclusion, abnormal bias in mMoM values may prompt aberrant application of median equations, and regular monitoring of these indicators may be important for quality control in prenatal screening. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the performance of high-resolution chromosomal microarray (CMA) as the standard diagnostic approach for genomic imbalances in pregnancies with increased risk based on combined first-trimester screening (cFTS).Methods: This was a retrospective study of genomic findings in a cohort of 575 consecutive pregnancies undergoing invasive testing because of a cFTS risk ≥ 1:300 on a publicly funded population-based screening program in the Central and Northern Regions of Denmark, between September 2015 and September 2016. Women with fetal nuchal translucency thickness ≥ 3.5 mm or opting for non-invasive prenatal testing (NIPT) were excluded. Comparative genomic hybridization was performed using a 180-K oligonucleotide array on DNA extracted directly from chorionic villus/amniocentesis samples. Genomic outcomes were reported in relation to cFTS findings.Results: Of the 575 pregnancies that underwent invasive testing, CMA detected 22 (3.8% (95% CI, 2.5-5.7%)) cases of trisomies 21, 18 and 13, 14 (2.4% (95% CI, 1.4-4.0%)) cases of other types of aneuploidy and 15 (2.6% (95% CI, 1.5-4.3%)) cases with a pathogenic or probably pathogenic copy number variant (CNV). Of the 15 CNVs, three were > 10 Mb and would probably have been detected by chromosomal analysis, but the other 12 would most probably not have been detected using conventional cytogenetic techniques; therefore, the overall detection rate of CMA (8.9% (95% CI, 6.8-11.5%)) was significantly higher than that estimated for conventional cytogenetic analysis (6.8% (95% CI, 5.0-9.1%)) (P = 0.0049). Reducing the cFTS risk threshold for invasive diagnostic testing to 1 in 100 or 1 in 50 would have led, respectively, to 60% or 100% of the pathogenic CNVs being missed.Conclusions: CMA is a valuable diagnostic technique that can identify an increased number of genomic aberrations in pregnancies at increased risk on cFTS. Limiting diagnostic testing to pregnancies with a risk above 1 in 100 or 1 in 50, as proposed in contingent NIPT/invasive testing models, would lead to a significant proportion of pathogenic CNVs being missed at first-trimester screening. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Study Question: Are fetal fraction, test failure rate and positive predictive value (PPV) of cell-free fetal DNA (cffDNA) testing different in singleton IVF conceptions compared to spontaneous conceptions?Summary Answer: Fetal fraction is significantly lower; test failure rate is higher and PPV of cffDNA testing is lower in singleton pregnancies conceived by IVF than those conceived spontaneously.What Is Already Known: cffDNA testing, which analyses circulating cffDNA in maternal blood, has very high accuracy for detection of trisomy 21 in the general obstetric population. Focused and conclusive evidence regarding the test characteristics of cffDNA testing in IVF conceived pregnancies is lacking.Study Design, Size, Duration: This was a retrospective cohort study including spontaneously and IVF conceived singleton pregnancies collected consecutively between April 2013 and November 2016. A total of 4633 spontaneously conceived and 992 IVF pregnancies were included.Participants/materials, Setting, Methods: The study was performed at an obstetric and gynecological ultrasound clinic in Melbourne, Australia. Participants had screening for trisomies 21, 18 and 13, as well as sex chromosome aneuploidies (SCA) performed with cffDNA testing after 10 weeks' gestation. Multivariate regression analysis was used to determine significant predictors of logarithmically transformed fetal fraction and test failure. Comparison of test characteristics between study groups was performed adopting a significance level of 5%.Main Results and the Role Of Chance: Median fetal fraction was lower (10.3% [interquartile range (IQR), 7.7-13.5] versus 11.9% [IQR, 9.1-15.0]; P = 0.005), test failure rate was higher (5.2 versus 2.2%; P < 0.001) and positive predictive value (PPV) for trisomies 18, 13 and SCA was poorer in IVF pregnancies compared to those spontaneously conceived. Multivariate linear regression analysis demonstrated that IVF conception, increased BMI, earlier gestational age and South and East Asian ethnicities were independent predictors of lower fetal fraction. Multiple logistic regression analysis found IVF conception and increased BMI to be independently associated with test failure. PPV was high for trisomy 21 in IVF conception (100.0%), but was lower for other trisomies when compared with the non-IVF population.Limitations Reasons For Caution: IVF details were unascertainable for 210 cases, as the information was not available through our data collection points. Inability to karyotype some cases at high-risk for SCA, due to patients' choice, and the occurrence of miscarriages and terminations, resulted in the exclusion of high-risk cases when calculating PPV. Pregnancy outcomes were not available in low-risk pregnancies and negative predictive values could not be calculated.Wider Implications Of the Findings: The limitations revealed by this work should be taken into account during pre-test counseling in pregnant women who conceive by IVF.Study Funding/competing Interest(s): No external source of financial support was provided for this research. The authors report no conflicts of interest. [ABSTRACT FROM AUTHOR]

Background: Down syndrome, which is the most common human chromosomal anomaly that can affect people of any race and age, can be diagnosed prenatally in most cases. Prenatal diagnosis via culture method is time-consuming; thus, genetic analysis has thus been introduced and is continually being developed for rapid prenatal diagnosis. For this reason, the effective use of microRNA profiling for the rapid analysis of prenatal amniotic fluid samples for the diagnosis of Down syndrome was investigated. Aims: To evaluate the expression levels of 14 microRNAs encoded by chromosome 21 in amniotic fluid samples and their utility for prenatal diagnosis of Down syndrome. Study Design: Case-control study. Methods: We performed invasive prenatal testing for 56 pregnant women; 23 carried fetuses with Down syndrome, and 33 carried fetuses with a normal karyotype. Advanced maternal age and increased risk for Down syndrome in the screening tests were indications for invasive prenatal testing. The age of gestation in the study and control groups ranged between 17 and 18 weeks. The expression levels of microRNA were measured by real-time polymerase chain reaction. Results: The expression levels of microRNA-125b-2, microRNA-155, and microRNA-3156 were significantly higher in the study group than in the control group. Conclusion: The presence of significantly dysregulated microRNAs may be associated with either the phenotype or the result of abnormal development. Further large-scale comparative studies conducted in a variety of conditions may bring novel insights in the field of abnormal prenatal conditions. [ABSTRACT FROM AUTHOR]

Background: While non-invasive prenatal testing (NIPT) for fetal aneuploidy is commercially available in many countries, little is known about how obstetric professionals in non-Western populations perceive the clinical usefulness of NIPT in comparison with existing first-trimester combined screening (FTS) for Down syndrome (DS) or invasive prenatal diagnosis (IPD), or perceptions of their ethical concerns arising from the use of NIPT.Methods: A cross-sectional survey among 327 obstetric professionals (237 midwives, 90 obstetricians) in Hong Kong.Results: Compared to FTS, NIPT was believed to: provide more psychological benefits and enable earlier consideration of termination of pregnancy. Compared to IPD, NIPT was believed to: provide less psychological stress for high-risk women and more psychological assurance for low-risk women, and offer an advantage to detect chromosomal abnormalities earlier. Significant differences in perceived clinical usefulness were found by profession and healthcare sector: (1) obstetricians reported more certain views towards the usefulness of NIPT than midwives and (2) professionals in the public sector perceived less usefulness of NIPT than the private sector. Beliefs about earlier detection of DS using NIPT were associated with ethical concerns about increasing abortion. Participants believing that NIPT provided psychological assurance among low-risk women were less likely to be concerned about ethical issues relating to informed decision-making and pre-test consultation for NIPT.Conclusions: Our findings suggest the need for political debate initially on how to ensure pregnant women accessing public services are informed about commercially available more advanced technology, but also on the potential implementation of NIPT within public services to improve access and equity to DS screening services. [ABSTRACT FROM AUTHOR]

Objectives To determine whether maternal plasma collected in cell-free DNA stabilizing tubes is suitable for measuring prenatal screening ‘serum’ markers. Methods Matched plasma and serum samples were collected from 41 second trimester and 42 first trimester non-Down’s syndrome pregnancies. Second trimester samples were tested for alpha-fetoprotein, unconjugated estriol, human chorionic gonadotropin, and inhibin-A (Beckman Coulter DxI immunoassay). First trimester samples were tested for human chorionic gonadotropin and pregnancy-associated plasma protein A. Method comparisons performed for each marker compared plasma and serum results. Down’s syndrome likelihood ratios in serum and plasma were compared. Results Plasma and serum results for all markers were highly correlated (r > 0.983) but for all, plasma results differed, usually by proportional amounts. After conversion to multiples of the median using sample type-specific medians, the logarithmic standard deviations in serum and plasma did not differ (all p > 0.37). Likelihood ratios for the first and second trimester marker combinations were highly correlated and closely agreed (log likelihood ratios range 1.005 to 1.032; 1.000 indicates complete agreement). Conclusions These results using specialized plasma collection tubes are similar to those of our earlier study showing that plasma collected in EDTA tubes is suitable for ‘serum’ Down’s syndrome screening. Laboratories must account for proportional changes by computing new plasma medians or modifying existing serum medians. Using a portion of the plasma from cell-free DNA collection tubes for ‘serum screening’ may have an advantage in programmes that are reflexively testing cell-free DNA, as only one sample type need be collected. [ABSTRACT FROM AUTHOR]

Objective: To examine the diagnostic accuracy of a previously developed model for the first-trimester combined test in screening for trisomies 21, 18 and 13.Methods: This was a prospective validation study of screening for trisomies 21, 18 and 13 by assessment of a combination of maternal age, fetal nuchal translucency, fetal heart rate and serum free β-human chorionic gonadotropin (β-hCG) and pregnancy-associated plasma protein-A (PAPP-A) at 11 + 0 to 13 + 6 weeks' gestation in 108 982 singleton pregnancies undergoing routine care in three maternity hospitals. A previously published algorithm was used to calculate patient-specific risks for trisomy 21, 18 and 13 in each patient. The detection rate (DR) and false-positive rate (FPR) at estimated risk cut-offs from 1 in 2 to 1 in 1000 were determined. The proportions of trisomies detected were compared to their expected values in different risk groups.Results: In the study population, there were 108 112 (99.2%) cases with normal fetal karyotype or birth of a phenotypically normal neonate and 870 (0.8%) cases with abnormal karyotype, including trisomy 21 (n = 432), trisomy 18 (n = 166), trisomy 13 (n = 56), monosomy X (n = 63), triploidy (n = 35) or other aneuploidy (n = 118). The screen-positive rates, standardized according to the maternal age distribution in England and Wales in 2011, of fetuses with abnormal or normal karyotype were compatible with those predicted from the previous model; at a risk cut-off of 1 in 100, the FPR was about 4% and the DRs for trisomies 21, 18 and 13 were 90%, 97% and 92%, respectively. There was evidence that the algorithm overestimated risk. This could, to some degree, reflect under-ascertainment in pregnancies ending in miscarriage or stillbirth.Conclusion: In a prospective validation study, the first-trimester combined test detected 90%, 97% and 92% of trisomies 21, 18 and 13, respectively, as well as > 95% of cases of monosomy X and triploidies and > 50% of other chromosomal abnormalities, at a FPR of 4%. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Background: The availability of non-invasive prenatal testing (NIPT) for aneuploidies is expanding rapidly throughout the world. Training health professionals to offer NIPT in a way that supports informed choice is essential for implementation. The aim of this study was to develop and evaluate a training package for health professionals to support the introduction of NIPT into clinical practice.Methods: Training on NIPT was offered to health professionals, primarily midwives, involved in Down syndrome screening and testing in eight hospitals located in England and Scotland as part of a research study evaluating the implementation of NIPT in the UK National Health Service. Training was evaluated using a mixed methods approach that included quantitative questionnaires at three time points and post-training qualitative interviews. The questionnaires measured confidence, self-perceived knowledge and actual knowledge about NIPT for Down syndrome. Interviews explored opinions about the training and experiences of offering NIPT.Results: The training provided to the health professionals was found to positively impact on their confidence in discussing NIPT with women in their clinic, and both their perceived and actual knowledge and understanding of NIPT was improved. Knowledge remained weak in four areas; cell-free fetal DNA levels increase with gestation; turnaround time for NIPT results; cell-free fetal DNA is placental in origin; and NIPT false positive rate.Conclusions: Training materials, including a lesson plan, PowerPoint presentation and written factsheet on NIPT, have been developed and evaluated for use in educating midwives and supporting the introduction of NIPT. Implementation of training should include a greater focus on the areas where knowledge remained low. Some groups of midwives will need additional training or support to optimise their confidence in discussing NIPT with women. [ABSTRACT FROM AUTHOR]

Background: Patient decision aids (PtDAs) help people make difficult, values-sensitive decisions. Prenatal screening for assessing the risk of genetic conditions in the fetus is one such decision and patient decision aids are rarely used in this clinical context. We sought to identify factors influencing pregnant women's use of a patient decision aid for deciding about prenatal screening for Down syndrome (DS).Methods: This qualitative study was embedded in a sequential mixed-methods research program whose main aim is to implement shared decision-making (SDM) in the context of prenatal screening for DS in the province of Quebec, Canada. We planned to recruit a purposive sample of 45 pregnant women with low-risk pregnancy consulting for prenatal care at three clinical sites. Participating women watched a video depicting a prenatal care follow-up during which a pregnant woman, her partner and a health professional used a PtDA to decide about prenatal screening for DS. The women were then interviewed about factors that would influence the use of this PtDA using questions based on the Theoretical Domains Framework (TDF). We performed content analysis of transcribed verbatim interviews.Results: Out of 216 eligible women, 100 agreed to participate (46% response rate) and 46 were interviewed. Regarding the type of health professional responsible for their prenatal care, 19 participants (41%) reported having made a decision about prenatal screening for DS with an obstetrician-gynecologist, 13 (28%) with a midwife, 12 (26%) with a family physician, and two (4%) decided on their own. We identified 54 factors that were mapped onto nine of the 12 TDF domains. The three most frequently-mentioned were: opinion of the pregnant woman's partner (n = 33, 72%), presentation of the PtDA by health professional and a discussion (n = 27, 72%), and not having encountered a PtDA (n = 26, 57%).Conclusion: This study allowed us to identify factors influencing pregnant women's use of a PtDA for prenatal screening for DS. Use of a PtDA by health professionals and patients is one step in providing the needed decision support and our study results will allow us to design an effective implementation strategy for PtDAs for prenatal screening for DS. [ABSTRACT FROM AUTHOR]

Background: Prenatal Diagnostics Testing is the only current method of clarifying suspicions on Down syndrome obtained as a result achieved through the increased risk screening. The pregnancy, by definition, is a period of great transformation, with multiple organic and psychological adaptation processes, while sensitivity touches high peaks and anything, as small as it could be, may disturb the equilibrium and cause psycho-emotional imbalances. Most often the diagnostic result of the screening is most likely to infirm the screening and will most probably reinstall the psycho-emotional stability, but mother's already anxious attitude may have already affected the child's future emotional development and behaviour. Methods: The present study is a narrative analysis, based on a collection of data from studies published in the databases of PubMed / Medline, SpringerLink, EBSCOhost, Elsevier and ResearchGate. Results: From reviewing the studies, there have been highlighted three themes: associated psychological effects, consequences and coping methods and practices and methods that can influence the psychological effects. Conclusion: The consequences and psychological effects, closely linked to the necessary diagnostic procedures and possible outcomes, require more interest from specialists which are now more focused on the diagnostic component. [ABSTRACT FROM AUTHOR]

Background: Down syndrome (trisomy 21) is a well-known cause of mental retardation. It can be diagnosed in early pregnancy. Scientists have made great strides in outlining the pathophysiologic mechanisms of mental retardation in Down syndrome. Much less has been published on human therapy. To cur knowledge, these are the first published cases of fetal therapy for Down syndrome. Methodology: Reports of three cases. In all cases, treatment was both biochemical (e.g. nutritional) and educational. In all cases, treatment was both befcre and after birth. Results: All children lacked the characteristic faces usually seen in the children with Down syndrome. This suggests a treatment effect before birth. All children had better than expected development. Discussion: Enhancement of development is preposed as a new therapeutic principle. Developing neurons exchange neurotrophic factors during development when they give or receive stimulation from other neurons. Neurons which receive neurotrophic stimulation survive, and those, which do not, are lost to apoptosis. The developmental therapeutic principle seeks to optimize brain development. Biochemical inputs (neurotransmitters, drugs, hormones, nutrients) and functional stimulation are integrated to optimize the growth and survival of neurons individually; other cells; subcellular organelles; and the brain as a whole. Treatment may be before and after birth, both biochemical and functional. These principles may be applied to Down syndrome, other conditions, and normal fetuses or children. Previously published: Baggot PJ and Baggot RM (2014). Fetal Therapy for Down Syndrome: Report of three cases and review of the literature. J Am Phys Surg 19(l):20-24. [ABSTRACT FROM AUTHOR]

Background: Health professionals are expected to engage pregnant women in shared decision making to help them make informed values-based decisions about prenatal screening. Patient decision aids (PtDAs) foster shared decision-making, but are rarely used in this context. Our objective was to identify factors that could influence health professionals to use a PtDA for decisions about prenatal screening for Down syndrome during a clinical pregnancy follow-up.Methods: We planned to recruit a purposive sample of 45 health professionals (obstetrician-gynecologists, family physicians and midwives) involved in the care of pregnant women in three clinical sites (15 per site). Participating health professionals first watched a video showing two simulated consecutive prenatal follow-up consultations during which a pregnant woman, her partner and a health professional used a PtDA about Down syndrome prenatal screening. Participants were then interviewed about factors that would influence their use of the PtDA. Questions were based on the Theoretical Domains Framework. We performed content analyses of transcribed verbatim interviews.Results: Out of 42 eligible health professionals approached, 36 agreed to be interviewed (86 % response rate). Of these, 27 were female (75 %), nine were obstetrician-gynecologists (25 %), 15 were family physicians (42 %), and 12 were midwives (33 %), with a mean age of 42.1 ± 11.6 years old. We identified 35 distinct factors reported by 20 % or more participants that were mapped onto 10 of the 12 of the Theoretical Domains Framework domains. The six most frequently mentioned factors influencing use of the PtDA were: 1) a positive appraisal (n = 29, 81 %, beliefs about consequences domain); 2) its availability in the office (n = 27, 75 %, environmental context and resources domain); 3) colleagues' approval (n = 27, 75 %, social influences domain); 4) time constraints (n = 26, 72 %, environmental context and resources domain); 5) finding it a relevant source of information (n = 24, 67 %, motivation and goals domain); and 6) not knowing any PtDAs (n = 23, 64 %, knowledge domain).Conclusions: Appraisal, PtDA availability, peer approval, time concerns, evidence and PtDA awareness all affect whether health professionals are likely to use a PtDA to help pregnant women make informed decision about Down syndrome screening. Implementation strategies will need to address these factors. [ABSTRACT FROM AUTHOR]

Objectives: First, to report the distribution of the fetal fraction of cell-free (cf) DNA and the rate of a failed cfDNA test result in trisomies 21, 18 and 13, by comparison with pregnancies unaffected by these trisomies, second, to examine the possible effects of maternal and fetal characteristics on the fetal fraction, and third, to consider the options for further management of pregnancies with a failed result.Methods: This was a cohort study of 10 698 singleton pregnancies undergoing screening for fetal trisomies 21, 18 and 13 by cfDNA testing at 10-14 weeks' gestation. There were 160 cases of trisomy 21, 50 of trisomy 18, 16 of trisomy 13 and 10 472 were unaffected by these trisomies. Multivariate regression analysis was used to determine significant predictors of fetal fraction and a failed cfDNA test result amongst maternal and fetal characteristics.Results: Fetal fraction decreased with increasing body mass index and maternal age, was lower in women of South Asian racial origin than in Caucasians and in assisted compared to natural conceptions. It increased with fetal crown-rump length and higher levels of serum pregnancy-associated plasma protein-A and free β-human chorionic gonadotropin. The median fetal fraction was 11.0% (interquartile range (IQR), 8.3-14.4%) in the unaffected group, 10.7% (IQR, 7.8-14.3%) in trisomy 21, 8.6% (IQR, 5.0-10.2%) in trisomy 18 and 7.0% (IQR, 6.0-9.4%) in trisomy 13. There was a failed result from cfDNA testing after first sampling in 2.9% of the unaffected group, 1.9% of trisomy 21, 8.0% of trisomy 18 and 6.3% of trisomy 13. In the cases with a failed result, 7% of women had invasive testing, mainly because of high risk from the combined test and/or presence of sonographic features suggestive of trisomies 18 and 13. All cases of trisomies were detected prenatally.Conclusions: In cases of a failed cfDNA test, the rate of trisomies 18 and 13, but not trisomy 21, is higher than in those with a successful test. In the management of such cases, the decision in favor of invasive testing should depend on the risk of prior screening and the results of detailed ultrasound examination. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Background: Uptake rates for Down syndrome screening in the Netherlands are low compared to other European countries. To investigate the low uptake, we explored women's reasons for participation and possible influences of national healthcare system characteristics. Dutch prenatal care is characterised by an approach aimed at a low degree of medicalisation, with pregnant women initially considered to be at low risk. Prenatal screening for Down syndrome is offered to all women, with a 'right not to know' for women who do not want to be informed on this screening. At the time this study was performed, the test was not reimbursed for women aged 35 and younger.Methods: We conducted a qualitative study to explore reasons for participation and possible influences of healthcare system characteristics. Data were collected via ten semi-structured focus groups with women declining or accepting the offer of Down syndrome screening (n = 46). All focus groups were audio- and videotaped, transcribed verbatim, coded and content analysed.Results: Women declining Down syndrome screening did not consider Down syndrome a condition severe enough to justify termination of pregnancy. Young women declining felt supported in their decision by perceived confirmation of their obstetric caregiver and reassured by system characteristics (costs and age restriction). Women accepting Down syndrome screening mainly wanted to be reassured or be prepared to care for a child with Down syndrome. By weighing up the pros and cons of testing, obstetric caregivers supported young women who accepted in the decision-making process. This was helpful, although some felt the need to defend their decision to accept the test offer due to their young age. For some young women accepting testing, costs were considered a disincentive to participate.Conclusions: Presentation of prenatal screening affects how the offer is attended to, perceived and utilised. By offering screening with age restriction and additional costs, declining is considered the preferred choice, which might account for low Dutch uptake rates. Autonomous and informed decision-making in Down syndrome screening should be based on the personal interest in knowing the individual risk of having a child with Down syndrome and system characteristics should not influence participation. [ABSTRACT FROM AUTHOR]

Objective: NIPT for fetal aneuploidy by digital PCR has been hampered by the large number of PCR reactions needed to meet statistical requirements, preventing clinical application. Here, we designed an octoplex droplet digital PCR (ddPCR) assay which allows increasing the number of available targets and thus overcomes statistical obstacles. Method: After technical optimization of the multiplex PCR on mixtures of trisomic and euploid DNA, we performed a validation study on samples of plasma DNA from 213 pregnant women. Molecular counting of circulating cell-free DNA was performed using a mix of hydrolysis probes targeting chromosome 21 and a reference chromosome. Results: The results of our validation experiments showed that ddPCR detected trisomy 21 even when the sample’s trisomic DNA content is as low as 5%. In a validation study of plasma samples from 213 pregnant women, ddPCR discriminated clearly between the trisomy 21 and the euploidy groups. Conclusion: Our results demonstrate that digital PCR can meet the requirements for non-invasive prenatal testing of trisomy 21. This approach is technically simple, relatively cheap, easy to implement in a diagnostic setting and compatible with ethical concerns regarding access to nucleotide sequence information. These advantages make it a potential technique of choice for population-wide screening for trisomy 21 in pregnant women. [ABSTRACT FROM AUTHOR]

Non-invasive prenatal testing (NIPT) for aneuploidy is currently only available in the UK through the private sector outside of the research arena. As part of an implementation study in the UK National Health Service we conducted a mixed methods study to assess women’s experience of being offered NIPT using validated measures of decisional conflict, decisional regret and anxiety. Clinical service preferences were also explored. Women with a Down syndrome screening risk >1:1000 were invited to take part in the study and offered NIPT, NIPT and invasive testing (for women with a risk above 1:150) or no further testing. A cross-sectional survey and semi-structured interviews were conducted at two time points; at the time of testing and one month following receipt of results (or equivalent for NIPT decliners). In total, 845 questionnaires and 81 interviews were analysed. The main motivation to accept NIPT was for reassurance (30.8%). Decisional conflict occurred in a minimal number of cases (3.8%), however, none of the participants experienced decisional regret. Around a third (29.9%) of women had elevated anxiety at the time of testing, including intermediate risk women who traditionally would not be offered further testing (54.4% high risk; 20.1% medium risk), a finding supported through the qualitative interviews where prolonged or additional anxiety was found to occur in some medium risk cases. Women were overwhelmingly positive about the opportunity to have a test that was procedurally safe, accurate, reduced the need for invasive testing and identified cases of Down syndrome that might otherwise have been missed. Reassurance was identified as the main motivator for accepting NIPT, particularly amongst medium risk women, with high risk women inclined to accept NIPT to inform decisions around invasive testing. The current turnaround time for test result was identified as a key limitation. All the women interviewed thought NIPT should be adopted as part of NHS clinical practice, with the majority favouring NIPT offered as a first-line test. Our study highlights the potential that NIPT has to positively impact women’s experience of prenatal testing for aneuploidy. [ABSTRACT FROM AUTHOR]

The article presents a ethical situation for physicians on creating strategies for teaching medical students on developing communication skills for patients with mental disabilities such as Down Syndrome, in undergoing prenatal risk assessment test and diagnosis of down syndrome.

Objective: To evaluate the clinical accuracy of the IONA® test for aneuploidy screening.Methods: This was a multicenter blinded study in which plasma samples from pregnant women at increased risk of trisomy 21 underwent cell-free DNA analysis utilizing the IONA test. For each sample, the IONA software generated a likelihood ratio and a maternal age-adjusted probability risk score for trisomies 21, 18 and 13. All results from the IONA test were compared against accepted diagnostic karyotyping.Results: A total of 442 maternal samples were obtained, of which 437 had test results available for analysis and assessment of clinical accuracy. The IONA test had a detection rate of 100% for trisomies 21 (n = 43; 95% CI, 87.98-100%), 18 (n = 10; 95% CI, 58.72-100%) and 13 (n = 5; 95% CI, 35.88-100%) with cut-offs applied to likelihood ratio (cut-off > 1 considered high risk for trisomy) and probability risk score incorporating adjustment for maternal age (cut-off ≥ 1/150 considered high risk for trisomy). The false-positive rate (FPR) was 0% for trisomies 18 and 13 with both analysis outputs. For trisomy 21, a FPR of 0.3% was observed for the likelihood ratio, but became 0% with adjustment for maternal age.Conclusion: This study indicates that the IONA test is suitable for trisomy screening in a high-risk screening population. The result-interpretation feature of the IONA software should facilitate wider implementation, particularly in local laboratories, and should be a useful addition to the current screening methods for trisomies 21, 18 and 13. [ABSTRACT FROM AUTHOR]

Objective: To assess the potential performance of screening for fetal trisomies 21, 18 and 13 by cell-free DNA (cfDNA) analysis of maternal blood using the IONA® test.Methods: This was a nested case-control study of cfDNA analysis of maternal plasma using the IONA test. Samples were obtained at 11-13 weeks' gestation, before chorionic villus sampling, from 201 euploid pregnancies, 35 with trisomy 21, four with trisomy 18 and two with trisomy 13. Laboratory personnel were blinded to the fetal karyotype.Results: Probability scores for trisomies 21, 18 and 13 were given for 241/242 samples analyzed. No probability score was provided for one (0.5%) euploid pregnancy because of low fetal fraction. In all 35 cases of trisomy 21 the probability score for trisomy 21 was > 95% and the scores for trisomies 18 and 13 were ≤ 0.0001%. In all four cases of trisomy 18, the probability score for trisomy 18 was > 77% and the scores for trisomies 21 and 13 were ≤ 0.0001%. In the two cases of trisomy 13, the probability score for trisomy 13 was > 59% and the scores for trisomies 21 and 18 were ≤ 0.0001%. In the 200 euploid pregnancies with a test result, the probability score was < 0.08% for trisomy 21, < 0.001% for trisomy 18 and < 0.002% for trisomy 13. Therefore, the IONA test detected 100% of all three trisomies, with a false-positive rate of 0%.Conclusion: The IONA test successfully differentiated all cases of trisomies 21, 18 and 13 from euploid pregnancies. [ABSTRACT FROM AUTHOR]

Background: Knowledge of the factors that influence maternal serum screening (MSS) service utilization can be used to develop health policies to promote equitable access to MSS and further diagnostic tests. The purpose of this study was to find the factors associated with utilization of MSS as well as the current status of service utilization in mainland China.Methods: This was a hospital-based cross-sectional study with respondents interviewed with a questionnaire designed based on Andersen's behavioral model. Descriptive statistics, univariate analysis, and multilevel logistic regression analysis were used to identify the factors associated with MSS utilization, and to explore potential methods to improve screening uptake.Results: A total of 8110 women who had given birth within the previous 7 days in one of 111 participating institutions from six provinces in mainland China were interviewed. Approximately 36% of the participants had used MSS. Women between 20 and 35 years, who resided in urban areas, were educated, were in a stable occupation, who had health knowledge, who attended maternal preparation classes, who had received eight or more prenatal checkups, who were from a region of higher social economic status, and who delivered in a tertiary healthcare institution were significantly more likely to use MSS than their counterparts. As compared with other factors, insufficient education is the single most important demographic factor for service underutilization.Conclusions: Efforts should not only be made to target the population that underuses MSS, but the overall organization of MSS service delivery should be assessed during policy development to make access to MSS equitable to the entire population of mainland China. [ABSTRACT FROM AUTHOR]

Objectives: Cell-free DNA (cfDNA) analysis of maternal blood for detection of trisomies 21, 18 and 13 is superior to other methods of screening but is expensive. One strategy to maximize performance at reduced cost is to offer cfDNA testing contingent on the results of the first-trimester combined test that is used currently. The objectives of this study were to report the feasibility of implementing such screening, to examine the factors affecting patient decisions concerning their options for screening and decisions on the management of affected pregnancies and to report the prenatal diagnosis of fetal trisomies and outcome of affected pregnancies following the introduction of contingent screening.Methods: We examined routine clinical implementation of contingent screening in 11,692 singleton pregnancies in two National Health Service (NHS) hospitals in the UK. Women with a risk ≥ 1 in 100 (high-risk group) were offered options of invasive testing, cfDNA testing or no further testing, and those with a risk between 1 in 101 and 1 in 2500 (intermediate-risk group) were offered cfDNA testing or no further testing. The trisomic status of the pregnancies was determined by prenatal or postnatal karyotyping or by examination of the neonates.Results: In the study population of 11,692 pregnancies, there were 47 cases of trisomy 21 and 28 of trisomies 18 or 13. Screening with the combined test followed by invasive testing for all patients in the high-risk group potentially could have detected 87% of trisomy 21 and 93% of trisomies 18 or 13, at a false-positive rate of 3.4%; the respective values for cfDNA testing in the high- and intermediate-risk groups were 98%, 82% and 0.25%. However, in the high-risk group, 38% of women chose invasive testing and 60% chose cfDNA testing; in the intermediate-risk group 92% opted for cfDNA testing. A prenatal diagnosis was made in 43 (91.5%) pregnancies with trisomy 21 and all pregnancies with trisomies 18 or 13. In many affected pregnancies the parents chose to avoid testing or termination and 32% of pregnancies with trisomy 21 resulted in live births.Conclusions: Screening for fetal trisomies by cfDNA analysis of maternal blood, contingent on the results of the combined test, can be implemented easily in routine clinical practice. In the high-risk group from the combined test, most but not all women chose cfDNA testing rather than invasive testing. Performance of screening for trisomy 21 was superior by the cfDNA test than by the combined test. However, prenatal detection of trisomies and pregnancy outcome depend not only on performance of screening tests but also on parental choice. [ABSTRACT FROM AUTHOR]

The present study explored current intrapersonal and interpersonal functioning of parents with a child diagnosed with Down syndrome. The participants included a national sample of participants who learned of their child's diagnosis either from prenatal screening/testing (n = 285) or from a postnatal diagnosis (n = 159). The main focus of this study included parents' coping strategies, hope, life satisfaction, relationship adjustment, and relationship satisfaction. These variables were explored using an Analysis of Variance (ANOVA) design. Similar to qualitative findings of limited differences between timing of awareness in diagnosis, the results indicated no statistically significant differences between the two groups on the measures of interest. Based on these findings, we provide initial quantitative evidence that parents who receive a postnatal diagnosis may not be at a large disadvantage compared to parents who had more time to prepare for a child with a Down syndrome diagnosis. The study provides an initial quantitative analysis of parents' levels of functioning related to their child's Down syndrome diagnosis based on the timing of the diagnosis, which is currently absent in the literature. [ABSTRACT FROM AUTHOR]

Study Question: How does a national prenatal screening program for Down syndrome (DS) perform in detecting sex chromosome abnormalities (SCAs)-Turner syndrome (TS), Klinefelter syndrome, 47,XXX and 47,XYY syndromes.Summary Answer: The SCA detection rate resulting from DS screening was below 50% for all four groups of SCAs.What Is Known Already: The detection rates of SCAs are higher in countries with DS screening. TS is associated with greater nuchal translucency (NT) and lower pregnancy-associated plasma protein-A (PAPP-A). However, specific detection rates of SCAs using prenatal DS screening have not been determined. No clear trend in PAPP-A, free beta human chorionic gonadotropin (β-hCG) and NT has been found in the remaining SCAs. Several lines of inquiry suggest that it would be advantageous for individuals with SCA to be detected early in life, leading to prevention or treatment of accompanying conditions. There is limited information about pre- and perinatal status that distinguishes SCA embryogenesis from normal fetal development.Study Design, Size, Duration: A register-based case-control study from the Danish Central Cytogenetic Register (DCCR), cross-linked with the Danish Fetal Medicine Database (DFMD), was performed from 2008 to 2012. Groups of SCAs were compared with DS and then matched with non-SCA controls to assess differences between these groups in prenatal markers and birth outcomes.Participants/materials, Setting, Methods: We included cases with prenatal and post-natal SCA karyotypes (n = 213), DS (n = 802) and 168 056 controls. We screened 275 037 individuals examined prenatally. We retrieved information regarding maternal age, NT, β-hCG and PAPP-A, as well as details regarding maternal and newborn characteristics.Main Results and the Role Of Chance: The DS screening procedure detected 87 per 100 000 TS (42% of expected), 19 per 100 000 Klinefelter syndrome (13% of expected), 16 per 100 000 47,XXX (16% of cases) and 5 per 100 000 47,XYY (5% of expected) SCAs, with an overall detection rate of 27%. Compared with controls, all four SCA groups showed significantly higher NT and lower PAPP-A compared with controls (all P < 0.01) and similar to DS. The legal abortion rate was high for all four syndromes (47,XXX: 24%; 47,XYY: 29%; Klinefelter syndrome: 48%, TS: 84%). For SCA fetuses carried to term, only TS fetuses had consistently lower birthweights and placenta weights than non-SCA controls (both P = 0.0001). A few SCA cases localized in DCCR could not be found in DFMD (n = 16).Limitations, Reason For Caution: Controls were matched on sex of the fetus of cases, meaning that all electively aborted fetuses (before week 12) were excluded, possibly reducing the diversity in the control group. We were not able to localize all diagnosed cases of SCA and DS in DFMD. Although these cases were present in DCCR, we were not able to account for the discrepancy. In addition, we suspect that several SCA children have not been diagnosed yet and future post-natal diagnosis of these cases would reduce the diagnostic yield reported here even further.Wider Implications Of the Findings: The prenatal detection rate is below 50% for all SCAs. The approach used for detecting DS cannot be extended to also include SCAs. In addition, all SCAs have low PAPP-A and increased NT, thus probably reflecting an abnormal embryogenesis. Growth retardation of TS fetuses is if anything more pronounced than previously reported, both when evaluating fetus and placenta.Study Funding/competing Interests: This study received support from Aarhus University and the Novo Nordisk Foundation. The authors have no competing interests that may be relevant to the study. [ABSTRACT FROM AUTHOR]

Background: Failed visualization of the fetal nasal bone (NB) by ultrasound at 11 -14 weeks of gestation is strongly associated with chromosomal abnormalities. Meanwhile, the incidence of the absent fetal NB in normal fetuses in the first trimester in mothers of different ethnic origins differs significantly. It is, therefore, important to assess ethnic variations in the first-trimester visualization of the fetal NB before introducing this marker into routine screening programs for aneuploidy. Objectives: The objectives of this study were to determine the NB length and the prevalence of the NB absence as well as calculating the likelihood ratio (LR) for the absence of the NB in normal fetuses of Iranian women undergoing first-trimester screening for trisomy 21. Patients and Methods: In 767 normal fetuses, the fetal profile was examined by ultrasound for the absence/presence of the NB. The NB length was also measured, and the LR for the NB absence was also determined. Results: The NB was absent in 2/767 (0.26%) of the fetuses. The mean length of the NB was 3.6 ± 0.69 mm for the fetuses of 11 -14 weeks gestational age. The LR value of the absent NB was equal to 250 in the normal fetuses of the Iranian population living in the North-West provinces. Conclusion: The low prevalence of the NB absence in normal fetuses in the present study is compatible with the larger size of the NB in Iranian people compared to other communities. Meanwhile, the reference range of the NB length in normal Iranian fetuses was established so that basic data could be recorded for further studies regarding the absence or presence of the NB in screening for chromosomal abnormalities (Down syndrome) within the Iranian population. [ABSTRACT FROM AUTHOR]

Background: Prenatal screening tests for Down syndrome (DS) are routine in many developed countries and new tests are rapidly becoming available. Decisions about prenatal screening are increasingly complex with each successive test, and pregnant women need information about risks and benefits as well as clarity about their values. Decision aids (DAs) can help healthcare providers support women in this decision. Using an environmental scan, we aimed to identify publicly available DAs focusing on prenatal screening/diagnosis for Down syndrome that provide effective support for decision making.Methods: Data sources searched were the Decision Aids Library Inventory (DALI) of the Ottawa Patient Decision Aids Research Group at the Ottawa Health Research Institute; Google searches on the internet; professional organizations, academic institutions and other experts in the field; and references in existing systematic reviews on DAs. Eligible DAs targeted pregnant women, focused on prenatal screening and/or diagnosis, applied to tests for fetal abnormalities or aneuploidies, and were in French, English, Spanish or Portuguese. Pairs of reviewers independently identified eligible DAs and extracted characteristics including the presence of practical decision support tools and features to aid comprehension. They then performed quality assessment using the 16 minimum standards established by the International Patient Decision Aids Standards (IPDASi v4.0).Results: Of 543 potentially eligible DAs (512 in DALI, 27 from experts, and four on the internet), 23 were eligible and 20 were available for data extraction. DAs were developed from 1996 to 2013 in six countries (UK, USA, Canada, Australia, Sweden, and France). Five DAs were for prenatal screening, three for prenatal diagnosis and 12 for both). Eight contained values clarification methods (personal worksheets). The 20 DAs scored a median of 10/16 (range 6-15) on the 16 IPDAS minimum standards.Discussion: None of the 20 included DAs met all 16 IPDAS minimum standards, and few included practical decision support tools or aids to comprehension.Conclusions: Our results indicate there is a need for DAs that effectively support decision making regarding prenatal testing for Down syndrome, especially in light of the recently available non-invasive prenatal screening tests. [ABSTRACT FROM AUTHOR]

Introduction: To evaluate the performance of first trimester nuchal translucency scan screening among pregnant women in Nigeria. Methods: A prospective observational and questionnaire based study involving 510 pregnant women between 11+0 and 13+6 weeks. Routine counselling and nuchal translucency measurement was conducted using the FMF, London guidelines. Chorionic villous sampling was done at NT = 2.5 mm or = 95th centile. Methods: A prospective observational and questionnaire based study involving 510 pregnant women between 11+0 and 13+6 weeks. Routine counselling and nuchal translucency measurement was conducted using the FMF, London guidelines. Chorionic villous sampling was done at NT = 2.5 mm or = 95th centile. Results: Five hundred and ten out of 542 (94.1%) were analysed, mainly referred by health care workers (87.2%) and from predominantly private facilities (94.3%). The number of NT scans performed increased in successive years with corresponding decrease in the mean scanning time. Scan was successfully completed at first attempt in (96.5%), with mean scanning time of 28.3 minutes. Nuchal translucency increases with gestational but not maternal age. The median and 95th centile at 11+0 week was 1.2mm and 1.7 mm and at 13+6 weeks was 1.5 mm and 2.2 mm. Using a cut-off of = 2.5 mm or = 95th centile, 17 (3.3%) screened positive. Three out of the 17 had invasive testing and 2 (DR = 66.7%) were confirmed trisomy 21, with a false positive rate of 5.9%. Although majority (86.4%) were willing to have invasive testing, only few (3 or 17.6%) of the high risk group had testing. Conclusion: The study demonstrated that NT scan is feasible as a screening tool in pregnancy in Nigeria. Measures of improving utilization include wider dissemination of information, provision of dedicated NT clinics and manpower training. [ABSTRACT FROM AUTHOR]

Background: Non-invasive prenatal testing (NIPT) for Down’s syndrome (DS) using cell free fetal DNA in maternal blood has the potential to dramatically alter the way prenatal screening and diagnosis is delivered. Before NIPT can be implemented into routine practice, information is required on its costs and benefits. We investigated the costs and outcomes of NIPT for DS as contingent testing and as first-line testing compared with the current DS screening programme in the UK National Health Service. Methods: We used a pre-existing model to evaluate the costs and outcomes associated with NIPT compared with the current DS screening programme. The analysis was based on a hypothetical screening population of 10,000 pregnant women. Model inputs were taken from published sources. The main outcome measures were number of DS cases detected, number of procedure-related miscarriages and total cost. Results: At a screening risk cut-off of 1∶150 NIPT as contingent testing detects slightly fewer DS cases, has fewer procedure-related miscarriages, and costs the same as current DS screening (around UK£280,000) at a cost of £500 per NIPT. As first-line testing NIPT detects more DS cases, has fewer procedure-related miscarriages, and is more expensive than current screening at a cost of £50 per NIPT. When NIPT uptake increases, NIPT detects more DS cases with a small increase in procedure-related miscarriages and costs. Conclusions: NIPT is currently available in the private sector in the UK at a price of £400-£900. If the NHS cost was at the lower end of this range then at a screening risk cut-off of 1∶150 NIPT as contingent testing would be cost neutral or cost saving compared with current DS screening. As first-line testing NIPT is likely to produce more favourable outcomes but at greater cost. Further research is needed to evaluate NIPT under real world conditions. [ABSTRACT FROM AUTHOR]

Objective To evaluate the impact of the introduction of a Down syndrome screening policy in England, including implementation of the first-trimester combined screening test, on reducing prenatal invasive diagnostic procedure rates. Methods All English cytogenetic laboratories were asked to submit data from the fiscal years 2003/2004 until 2011/2012 on all samples received from prenatal invasive procedures, including those that were undertaken following a higher-risk Down syndrome screening result. Results There was a gradual decline in the number of invasive procedures undertaken subsequent to a positive Down syndrome screening result in England, from 36?968 in 2003/2004 to 11?446 in 2008/2009, with only a relatively small subsequent decrease, to 10?215, in 2011/2012. This corresponds to a 72% reduction in the number of referrals received by the cytogenetic laboratories over a 9-year period and correlates with the national policy of implementing the combined screening test in place of second-trimester screening, which has reduced the overall screen-positive rate to 3.1% from an initial level of 6.0%. Conclusions Implementation of a national Down syndrome screening policy based on the combined screening test has significantly reduced the number of invasive tests performed. However, as the combined screening test has become the replacement for second-trimester testing and has been almost completely implemented it appears that improvements in screening using current approaches may have reached their limits. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 40-year-old pregnant woman, who was referred to clinic at 32 weeks' gestation because of oligohydramnios and severe intrauterine growth restriction (IUGR). The patient was diagnosed for confined placental mosaicism (CPM) of double trisomies 9 and 21. The article discusses that CPM of trisomy 9 have been reported with features of skeletal abnormalities and neurodevelopmental impairment.

The author comments on the method of test interpretation for suboptimal Down's syndrome screening. He wrote a paper urging the combination of biochemical and ultrasound screening for Down's syndrome into a single late first-trimester test. At that time, the method of test interpretation hinders rapprochement. He suggests three principles of screening needed in evaluating the optimal way to allow for gestation and calculate risks.

Background: DNA-based non-invasive prenatal testing (NIPT) using maternal blood constitutes an emerging technology for the detection of Down syndrome (DS). The aim of the study was to conduct a cost-effectiveness analysis to evaluate the economic costs and health implications of the introduction of NIPT based on cell-free foetal DNA analysis through different screening strategies for the detection of DS. Methods: An analytical short-term decision model was developed, from the payer´s perspective (Spanish National Health Service). The main outcome measure was the number of DS cases detected. Secondary measures included associated miscarriages, women undergoing current screening, women undergoing NIPT, positive NIPT and invasive procedures performed. The study setting was the Spanish National Health Service. Three strategies were compared: (a) first- and second-trimester screening (current screening); (b) NIPT as contingent testing; and (c) NIPT as first-line testing. Modelling was based on a hypothetical cohort of 100,000 Spanish pregnant women. Population data were obtained from the database of the Basque Antenatal Screening Programme. Deterministic sensitivity analyses were performed to assess variations in the cost of NIPT, screening risk cut-off, screening uptake-rate and rate of failure of NIPT. Results: NIPT as contingent testing (strategy b) led to fewer miscarriages following invasive procedures and a slight reduction in the number of DS cases detected compared to current screening. However, lowering the screening cut-off to ≥ 1:500 would improve the overall effectiveness of NIPT as contingent testing, increasing the number of DS cases detected and decreasing foetal losses as compared to the current screening, despite there would be an extra-cost of 3.5%. When NIPT was used as first-line testing (strategy c), the screening would be more effective but also more expensive, with incremental cost-effectiveness ratios (ICERs) per additional case of DS detected of €1,299,763 and €1,232,763, compared with strategies a and b, respectively. Results were sensitive to the different parameters considered in the analysis. Conclusions: Both, as first-line testing and as contingent testing when screening cut-off was lowered ≥ 1:500, NIPT would lead to more favourable outcomes as compared to the current screening (both in terms of DS cases detected and miscarriages avoided), but at a greater cost. [ABSTRACT FROM AUTHOR]