Uptake of fetal aneuploidy screening after the introduction of the non-invasive prenatal test: A national population-based register study

Uptake rates for non-invasive prenatal screening for single-gene disorders associated with advanced paternal age

This study sought to quantify uptake rates of non-invasive prenatal screening for de novo single-gene disorders (NIPS-SGD) in pregnant subjects whose reproductive partner is of advanced paternal age (APA) and to determine individual parameters associated with higher test uptake rates. A cross-sectional study was performed of pregnant subjects who received prenatal genetic counseling at a mid-size tertiary care center and were offered NIPS-SGD for APA (defined as 45 or older at delivery) between June 1, 2017 and April 13, 2021. We included non-anomalous, singleton gestations who conceived without donor egg/sperm. The outcome was measured as subjects who elected to do NIPS-SGD versus subjects who declined. Multivariable logistic regression was used to develop a model to discriminate between those who opted for testing and those who did not. 186 subjects were offered NIPS-SGD and met inclusion criteria. 70 had testing and 116 declined. Overall uptake rate was 38%. Several individual parameters were associated with higher test uptake including utilization of other screenings such as NIPS for aneuploidy (OR 3.4), carrier screening (OR 7.0) and invasive diagnostic testing (OR 8.4), presence of reproductive partner (OR 4.3), medicaid insurance (OR 2.6), and counseling at an offsite location (OR 2.0). AUC for the final regression model predicting NIPS-SGD uptake was 0.79. Based on this study, subjects who are information seekers and who opt for other prenatal screenings are more likely to pursue NIPS-SGD for de novo conditions associated with APA.

Comparing the Introduction and Implementation of Noninvasive Prenatal Testing (NIPT) in Japan, the Netherlands, and the United States: An Integrative Review

Previous studies suggest that NIPT's implementation differed widely across countries but offer limited insight into what shaped these differences. To address this gap, we conducted an in-depth analysis of how NIPT was incorporated into prenatal care in the US, the Netherlands, and Japan-countries with similar economic status-to identify actionable lessons. We conducted an integrative literature review on the process of introducing and implementing NIPT, stakeholders' roles, documented considerations in the decision to introduce NIPT, implementation choices, and NIPT uptake. We included 184 sources, including white and gray literature and non-English sources. We identified 17 considerations that were documented to have influenced the decision whether to introduce NIPT across five domains: clinical considerations, ethical considerations and societal values, financial considerations, demand and capacity and applicable oversight. Fewer factors seem to have been considered in the US as compared to Japan or the Netherlands. Countries subsequently made choices on how to implement NIPT-we identified 35 such choices. While most of the identified choices were eventually considered by all three countries, they made different decisions (e.g., on out-of-pocket costs). In 2022, the estimated proportion of pregnant persons who used NIPT was 58% in the Netherlands, 49% in the US, and 9% in Japan. While differences in cultural values, population characteristics, and healthcare systems explain some variation, we identified other more adaptable aspects of the decision-making process (e.g., oversight) that may be useful for countries introducing NIPT or similar technologies to consider.

Methylome profiling of cell-free DNA during the early life course in (un)complicated pregnancies using MeD-seq: Protocol for a cohort study embedded in the prospective Rotterdam periconception cohort

INTRODUCTION

Placental DNA methylation differences have been associated with timing in gestation and pregnancy complications. Maternal cell-free DNA (cfDNA) partly originates from the placenta and could enable the minimally invasive study of placental DNA methylation dynamics. We will for the first time longitudinally investigate cfDNA methylation during pregnancy by using Methylated DNA Sequencing (MeD-seq), which is compatible with low cfDNA levels and has an extensive genome-wide coverage. We aim to investigate DNA methylation in placental tissues and cfDNA during different trimesters in uncomplicated pregnancies, and in pregnancies with placental-related complications, including preeclampsia and fetal growth restriction. Identified gestational-age and disease-specific differentially methylated regions (DMRs) could lead to numerous applications including biomarker development.

METHODS AND ANALYSIS

Our study design involves three sub-studies. Sub-study 1 is a single-centre prospective, observational subcohort embedded within the Rotterdam Periconception cohort (Predict study). We will longitudinally collect maternal plasma in each trimester and during delivery, and sample postpartum placentas (n = 300). In sub-study 2, we will prospectively collect first and second trimester placental tissues (n = 10 per trimester). In sub-study 3 we will retrospectively collect plasma after non-invasive prenatal testing (NIPT) in an independent validation case-control cohort (n = 30-60). A methylation-dependent restriction enzyme (LpnPI) will be used to generate DNA fragments followed by sequencing on the Illumina NextSeq2000 platform. DMRs will be identified in placental tissues and cell types, and in cfDNA related to gestational-age or placental-related complications. (Paired) placental methylation profiles will be correlated to DMRs in cfDNA to aid tissue-of-origin analysis. We will establish a methylation score to predict associated diseases.

DISCUSSION

This study will provide insights in placental DNA methylation dynamics in health and disease, and could lead to clinical relevant biomarkers.

Non-invasive prenatal testing: Assessing the availability and accessibility of information available to the pregnant population within the Republic of Ireland

OBJECTIVE

While non-invasive prenatal testing (NIPT) has been widely adopted throughout Europe, Australia, and the USA, population level access to NIPT varies considerably. Ireland has no national screening programme for fetal anomalies, although NIPT is available from out-of-country providers. We aimed to describe the availability of NIPT in Ireland and the quality of information available online from NIPT providers.

METHODS

Information available online from NIPT providers in the Republic of Ireland was analysed by examining all healthcare facilities websites and reviewing private health insurance directories. Data on information provided by NIPT providers was collected by two independent researchers from April to May 2023.

RESULTS

Four of the 19 maternity hospitals/units in Ireland had information on NIPT on their websites, with three including an explanation of NIPT, testing accuracy, and associated fees (€380-480). Twenty private clinics led by obstetric consultants advertised NIPT online, of which seventeen clinics included an explanation of NIPT, testing accuracy, and associated fees (€380-€650). Twenty-nine other providers, which included ultrasound clinics, direct-to-consumer laboratory testing, and General Practitioners, advertised NIPT with 18 of these providers including an explanation of NIPT, testing accuracy, and associated fees (€179-€630).

CONCLUSION

While there is apparent demand for NIPT and it is available in Ireland, there is disparity between providers on the type and quality of information available. Difficulty obtaining accessible information, the associated financial costs and location of providers advertising NIPT are likely to be barriers to accessing NIPT. A national screening programme for aneuploidy should be considered to ensure both equitable access to and reliable information about prenatal screening.

Prenatal cell-free DNA testing of women with pregnancy-associated cancer: a retrospective cross-sectional study

Background

Incidentally, the non-invasive prenatal test (NIPT) shows chromosomal aberrations suspicious of a maternal malignancy, especially after genome-wide testing. The aim of this study is to determine how many cases of cancer in pregnancy are diagnosed or missed with NIPT and whether in retrospect subtle changes in NIPT results could have detected cancer.

Methods

We identified Dutch patients diagnosed in 2017-2021 with pregnancy-associated cancer from the International Network on Cancer, Infertility and Pregnancy (INCIP) Registry, who underwent NIPT in the Dutch NIPT implementation study (TRIDENT-2). We retrospectively assessed how many of these women showed a malignancy suspicious-NIPT, their tumour types and -stages, and the time interval between NIPT and cancer diagnosis.

Findings

Of 143 women with pregnancy-associated cancer, we included 65 patients that underwent an NIPT. Fifty-four women had a solid tumour and 11 a haematological malignancy. Sixteen (24.6%) NIPTs were malignancy suspicious (15 genome-wide, one targeted). All 10 haematological cancer patients with genome-wide NIPT had a malignancy suspicious-NIPT, irrespective of the disease stage. Only five patients with a solid tumour had a genome-wide malignancy suspicious-NIPT (4/5 advanced cancer stage III or IV). The mean time between date of NIPT and cancer diagnosis was significantly shorter after a malignancy suspicious-NIPT compared to a non-suspicious-NIPT, respectively 49.9 days (± SD 31.8) and 100.7 days (± SD 74.9), p = 0.001.

Interpretation

All genome-wide NIPT in women with pregnancy-associated haematological malignancies were malignancy suspicious. Women with a solid tumour showed a malignancy suspicious-NIPT in only a minority of cases, mainly the advanced stages.

Funding

None.

Vocational identity in decision-making for terminating/continuation of pregnancy following non-invasive prenatal testing and hypothetical diagnosis among Japanese university students

The use of prenatal testing in Japan is expected to increase. However, there are ethical concerns regarding pregnancy termination upon the detection of fetal chromosomal abnormalities, such as Down syndrome. Furthermore, factors associated with decision-making following a positive result of Down syndrome after prenatal screening remain unclear. Therefore, we aimed to evaluate the association between decision-making among university students following a hypothetical positive result of Down syndrome in prenatal screening and their perception of their future career development defined as vocational identity. This cross-sectional study included 256 individuals (109 men, 143 women, and four who preferred not to answer). Self-anonymous semi-structured questionnaires were distributed to collect information regarding socio-demographic characteristics, vocational identity, and decision-making following a positive prenatal screening result of Down syndrome. Vocational identity was assessed using the Vocational Identity Measure. Women students were more likely to intend to continue the pregnancy (76.9%, p < 0.05); however, students without siblings (68.2%, p < 0.01) and men and women students with higher scores for vocational identities who were raised in an academically oriented family were more likely to intend to terminate the pregnancy (p < 0.05). Therefore, gender and vocational identity were associated with decision-making following a positive result of Down syndrome. Further qualitative and quantitative studies on factors associated with decision-making following a positive result of Down syndrome are necessary to eliminate the burden and social barrier, including gender division of labor and the effect of vocational career for people wishing to parent a child with Down syndrome.

Primary care professionals' views on population-based expanded carrier screening: an online focus group study

BACKGROUND

Population-based expanded carrier screening (ECS) involves screening for multiple recessive diseases offered to all couples considering a pregnancy or during pregnancy. Previous research indicates that in some countries primary care professionals are perceived as suitable providers for ECS. However, little is known about their perspectives. We therefore aimed to explore primary care professionals' views on population-based ECS.

METHODS

Four online focus groups with 14 general practitioners (GPs) and 16 community midwives were conducted in the Netherlands.

RESULTS

Our findings highlight various perspectives on the desirability of population-based ECS. Participants agreed that ECS could enhance reproductive autonomy and thereby prevent suffering of the child and/or parents. However, they also raised several ethical, societal, and psychological concerns, including a tendency towards a perfect society, stigmatization, unequal access to screening and negative psychosocial consequences. Participants believed that provision of population-based ECS would be feasible if prerequisites regarding training and reimbursement for providers would be fulfilled. most GPs considered themselves less suitable or capable of providing ECS, in contrast to midwives who did consider themselves suitable. Nevertheless, participants believed that, if implemented, ECS should be offered in primary care or by public health services rather than as hospital-based specialized care, because they believed a primary care ECS offer increases access in terms of time and location.

CONCLUSIONS

While participants believed that an ECS offer would be feasible, they questioned its desirability and priority. Studies on the desirability and feasibility of population-based ECS offered in primary care or public health settings are needed.

Adverse pregnancy outcome in fetuses with early increased nuchal translucency: prospective cohort study

OBJECTIVES

An increased nuchal translucency (NT) thickness of ≥ 3.5 mm is a well-established marker for congenital anomalies and adverse pregnancy outcome between 11 and 14 weeks' gestation, but little is known about its performance as a screening tool before 11 weeks. We aimed to investigate, in a prospective setting, whether fetuses with increased NT before 11 weeks are at risk for adverse pregnancy outcome.

METHODS

This was a prospective cohort study including pregnant women with a viable fetus with NT ≥ 2.5 mm and a crown-rump length (CRL) < 45 mm. All included women were referred to our fetal medicine unit (FMU) and scheduled for a follow-up scan where the NT was remeasured after 1 week when the CRL was > 45 mm. Two groups were evaluated: cases with a normalized NT (< 3.5 mm) and cases with persistently increased NT (≥ 3.5 mm). The cases were monitored until 4 weeks after delivery. The main outcome was a composite adverse outcome of aneuploidy, other genetic disorders, structural anomalies and pregnancy loss. We performed subgroup analyses of NT thickness at inclusion and normalized or persistently increased NT at follow-up.

RESULTS

The study included 109 cases, of which 39 (35.8%) had an adverse pregnancy outcome. Of these, 64.1% (25/39) were aneuploid, corresponding to 22.9% (25/109) of the total study population. In the subgroups of NT thickness at inclusion of 2.5-3.4 mm, 3.5-4.4 mm and ≥ 4.5 mm, an adverse outcome was reported in 22.0% (9/41), 40.0% (18/45) and 52.2% (12/23), respectively. In fetuses with a normalized NT and without ultrasound abnormalities at the follow-up scan, the incidence of adverse outcome was 8.5% (5/59), of which 5.1% (3/59) cases were aneuploid.

CONCLUSIONS

Fetuses with an early increased NT thickness are at considerable risk of an adverse pregnancy outcome, even if the NT normalizes after 11 weeks. Not all congenital anomalies can be diagnosed with routine first-trimester screening, such as non-invasive prenatal testing and/or a first-trimester anomaly scan. Therefore, expectant parents should always be referred to a FMU for detailed ultrasonography. Invasive prenatal testing should be offered if an increased NT of ≥ 2.5 mm is observed before 11 weeks' gestation. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Eliminating first trimester combined testing: Consequences for early detection of significant fetal anomalies

OBJECTIVE

To determine whether implementation of cell-free DNA (cfDNA) testing for aneuploidy as a first-tier test and subsequent abolition of first trimester combined testing (FCT) affected the first trimester detection (<14 weeks) of certain fetal anomalies.

METHODS

We performed a geographical cohort study in two Fetal Medicine Units between 2011 and 2020, including 705 fetuses with prenatally detected severe brain, abdominal wall and congenital heart defects. Cases were divided into two groups: before (n = 396) and after (n = 309) cfDNA introduction. The primary outcome was the first trimester detection rate (<14 weeks) overall and for non-chromosomal anomalies solely.

RESULTS

Overall, gastroschisis, AVSD and HLHS were detected more often in the first trimester in the before group compared to the after group, respectively 54.5% versus 18.5% (p = 0.004), 45.9% versus 26.9% (p = 0.008) and 30% versus 3.4% (p = 0.005). After exclusion of chromosomal anomalies identifiable through cfDNA testing, the detection of AVSD remained higher in the before group (43.3% vs. 9.5%, p = 0.02), leading to a possible earlier gestation at termination. The termination of pregnancy (TOP) rate did not differ among the groups. In the after group, referrals for suspected anomalies following a dating scan between 11 and 14 weeks significantly increased from 17.4% to 29.1% (p < 0.001).

CONCLUSION

This study underscores the value of a scan dedicated to fetal anatomy in the first trimester as we observed a decline in the early detection of certain fetal anomalies (detectable in the first trimester) subsequent to the abolition of FCT.

Current controversies in prenatal diagnosis: Noninvasive prenatal testing should replace other screening strategies for fetal trisomies 13, 18, 21

This is a written summary of the oral debate presented at the International Society for Prenatal Diagnosis annual conference in Edinburgh in 2023. The topic under debate is whether noninvasive prenatal testing (NIPT) using cell-free fetal DNA should replace other screening strategies for the detection of fetal trisomies 13, 18, 21. There is no disagreement that NIPT is far more sensitive and has better positive predictive values for identifying trisomies 13, 18, and 21 than traditional screening approaches using biochemical markers and measurement of nuchal translucency. The major issue lies in the potential adverse consequences associated with abandoning traditional screening methods. The source of disagreement stems primarily from whether you consider the role of ultrasound in the context of screening to be strictly for nuchal translucency measurement or whether it should be combined with a fetal anatomy scan. The debate featured two experts who presented evidence in favor of each argument.

Informed choice and routinization of the second-trimester anomaly scan: a national cohort study in the Netherlands

BACKGROUND

Since 2007 all pregnant women in the Netherlands are offered the second-trimester anomaly scan (SAS) in a nationwide prenatal screening program. This study aims to assess the level of informed choice of women opting for the SAS and to evaluate the presence of routinization 16 years after its implementation. It further explores decisional conflict and women's decision making.

METHODS

This prospective national survey study consisted of an online questionnaire which was completed after prenatal counseling and before undergoing the SAS. Informed choice was measured by the adapted multidimensional measure of informed choice (MMIC) and was defined in case women were classified as value-consistent, if their decision for the SAS was deliberated and made with sufficient knowledge.

RESULTS

A total of 894/1167 (76.6%) women completed the questionnaire. Overall, 54.8% made an informed choice, 89.6% had good knowledge, 59.8% had deliberated their choice and 92.7% held a positive attitude towards the SAS. Women with low educational attainment (p=0.004) or respondents of non-Western descent (p=0.038) were less likely to make an informed choice. Decisional conflict was low, with a significantly lower decisional conflict score in women that made an informed choice (p<0.001). Most respondents (97.9%) did not perceive pressure to undergo the SAS.

CONCLUSIONS

Our study showed a relatively low rate of informed choice for the SAS, due to absence of deliberation. Therefore, some routinization seem to be present in the Netherlands. However, most women had sufficient knowledge, did not perceive pressure and experienced low decisional conflict.

Navigation of Prenatal Care With Sex Discordance Between Cell-free DNA and Ultrasound Findings

The utilization of cell-free DNA (cfDNA) screening has expanded rapidly across the age spectrum of pregnant persons. With cfDNA's widespread adoption, genetic fetal sex is now often known before a phenotypic assessment on anatomic survey. CfDNA detects sex discordance in 1/1500 to 2000 pregnancies. Upon detection of sex discordance, lab error or other factors should first be assessed. Once other causes have been ruled out, this may indicate an underlying disorder/difference in sex development. A multidisciplinary team should coordinate diagnosis, treatment, and support for the family. This review discusses the diagnostic workup, emphasizing the multidisciplinary counseling and management of disorder/differences in sex development.

Non-Invasive Prenatal Testing (NIPT): Reliability, Challenges, and Future Directions

Non-invasive prenatal testing was first discovered in 1988; it was primarily thought to be able to detect common aneuploidies, such as Patau syndrome (T13), Edward Syndrome (T18), and Down syndrome (T21). It comprises a simple technique involving the analysis of cell-free foetal DNA (cffDNA) obtained through maternal serum, using advances in next-generation sequencing. NIPT has shown promise as a simple and low-risk screening test, leading various governments and private organizations worldwide to dedicate significant resources towards its integration into national healthcare initiatives as well as the formation of consortia and research studies aimed at standardizing its implementation. This article aims to review the reliability of NIPT while discussing the current challenges prevalent among different communities worldwide.

Financial contribution as reason to opt out of non-invasive prenatal testing

OBJECTIVE

First trimester non-invasive prenatal testing (NIPT) provides pregnant women with a reliable, non-invasive method to screen for fetal aneuploidies. In the Netherlands, there is a nationwide prenatal screening program in which pregnant women and their partners are counseled about their options around 10 weeks of pregnancy. The first trimester and second trimester scan are fully reimbursed but the NIPT has an own financial contribution of €175 per participant, irrespective of type of insurance. The arguments for this own contribution are fear of uncritical use of NIPT or routinization. NIPT has a relatively stable uptake of 51%, against over 95% for second trimester anomaly scan. We aimed to explore the effect of this financial contribution on the decision to opt out of NIPT.

STUDY DESIGN

We performed a survey among 350 pregnant women undergoing a second trimester anomaly scan in our center, Amsterdam UMC, between January 2021 and April 2022. All pregnant women who declined NIPT in the first trimester, were asked to participate and answered 11-13 questions about the decision-making process, the reasons to opt out and the financial contribution.

RESULTS

Information about NIPT was desired in 92% of women and 96% felt sufficiently informed. Most women took the decision not to perform NIPT with their partner and did not experience difficulties in taking this decision. The most important reason to decline NIPT was: "Every child is welcome" (69%). "The test was too expensive" was answered in 12% and was significantly correlated with lower maternal age. Additionally, one in five women (19%) said they would have done NIPT if it had been for free, which was significantly higher in younger women.

CONCLUSIONS

The own financial contribution plays a role in the decision-making to decline NIPT and partly explains the low uptake in the Netherlands. This suggests that there is no equal access to fetal aneuploidy screening. To overcome this inequality, this own contribution should be abandoned. We speculate that this will have a positive effect on the uptake, which will increase to at least 70% and potentially 94%.

Population monitoring of trisomy 21: problems and approaches

Trisomy 21 (Down syndrome) is the most common autosomal aneuploidy among newborns. About 90% result from meiotic nondisjunction during oogenesis, which occurs around conception, when also the most profound epigenetic modifications take place. Thus, maternal meiosis is an error prone process with an extreme sensitivity to endogenous factors, as exemplified by maternal age. This contrasts with the missing acceptance of causal exogenous factors. The proof of an environmental agent is a great challenge, both with respect to ascertainment bias, determination of time and dosage of exposure, as well as registration of the relevant individual health data affecting the birth prevalence. Based on a few exemplary epidemiological studies the feasibility of trisomy 21 monitoring is illustrated. In the nearer future the methodical premises will be clearly improved, both due to the establishment of electronic health registers and to the introduction of non-invasive prenatal tests. Down syndrome is a sentinel phenotype, presumably also with regard to other congenital anomalies. Thus, monitoring of trisomy 21 offers new chances for risk avoidance and preventive measures, but also for basic research concerning identification of relevant genomic variants involved in chromosomal nondisjunction.

Neonatal mortality and morbidity in Down syndrome in the time of prenatal aneuploidy testing: a retrospective cohort study

The total uptake of prenatal aneuploidy screening for Down syndrome (DS) is increasing worldwide. As a result of increasing prenatal diagnosis of DS and subsequent termination of pregnancy, livebirth prevalence of DS is decreasing. The aim of this study is to explore the impact of an increasing uptake of prenatal aneuploidy screening on the neonatal mortality and morbidity in DS. This is a retrospective cohort study of 253 neonates with DS born between 2012 and 2018 that were seen at the outpatient clinic of five hospitals in the Netherlands. The medical files were reviewed for maternal and neonatal characteristics and neonatal morbidities. The Dutch national birth registry (Perined) provided mortality numbers of neonates with DS. The results were interpreted in the context of other published studies. Neonatal mortality in DS remained stable, ranging from 1.4 to 3.6%. A congenital heart defect (CHD) was found in 138 of the 251 neonates (55.0%) with atrial septal defect, atrioventricular septal defect, and ventricular septal defect being the most common. The type of CHD in DS did not change over time. Gastro-intestinal defects were present in 22 of the 252 neonates with DS (8.7%), with duodenal atresia as the most reported anomaly. Persistent pulmonary hypertension of the neonate (PPHN) was found in 31 of the 251 infants (12.4%).  Conclusions: Although uptake of prenatal aneuploidy screening increased, neonatal mortality and morbidity in DS appears to be stable. An increased incidence of PPHN was found. What is Known: • The total uptake of prenatal aneuploidy screening for Down syndrome is increasing worldwide. • As a result of increasing prenatal diagnosis of Down syndrome and subsequent termination of pregnancy, the livebirth prevalence of Down syndrome is decreasing. What is New: • Although uptake of prenatal aneuploidy screening increased, neonatal mortality and morbidity in Down syndrome appears to be stable. • An increased incidence of persistent pulmonary hypertension of the neonate was found.

Issues associated with possible implementation of Non-Invasive Prenatal Testing (NIPT) in first-tier screening: A rapid scoping review

In recent years, as the implementation and use of Non-Invasive Prenatal Testing (NIPT) have increased, the cost of the test has been decreasing. The cost of NIPT is expected to fall further in the upcoming years. As a result of the decreasing cost of NIPT, many jurisdictions may change their prenatal screening policies toward abandoning serum-based screening and instead, implement and support NIPT as the first-tier screening for all women. There are several concerns in replacing first-trimester screening with NIPT. In this scoping review, we aimed to map the existing knowledge about possible issues in the systematic implementation of NIPT as the primary method of first-tier screening and to assess if any jurisdiction has altered its policy and discontinued serum-based prenatal screening in exchange for NIPT. The Medline database (Ovid) and Google Scholar was searched and all the studies discussing, investigating, or reporting on the systematic implementation of NIPT as the primary method of first-tier screening were included. All the studies went through a two-stage screening process and included full-text articles were reviewed. We did not find any articles indicating a country or region that replaced traditional prenatal screening by NIPT. The included articles were charted, and the data about the possible issues in the systematic implementation of NIPT as the primary method of first-tier screening are summarized narratively and presented in tables in four categories. The findings of this scoping review may be informative for stakeholders and policymakers regarding recent changes in NIPT implementation policies around the world and may aid with developing policy for NIPT implementation with a broader perspective.

Non-invasive prenatal testing in Germany: a unique ethical and policy landscape

Non-invasive prenatal testing (NIPT) has been available commercially in Europe since approximately 2012. Currently, many countries are in the process of integrating NIPT into their publicly funded healthcare systems to screen for chromosomal aneuploidies such as trisomy 21 (Down syndrome), with a variety of implementation models. In 2019, the German Federal Joint Committee (G-BA), which plays a significant role in overseeing healthcare decisions in Germany, recommended that NIPT be reimbursed through public insurance. Following this recommendation, NIPT will be offered on a case-by-case basis, when a pregnant woman, after being counselled, makes an informed decision that the test is necessary in her personal situation. This model differs significantly from many other European countries, where NIPT is being implemented either as a first-tier screening offer available for all pregnancies, or a contingent screen for those with a high probability of foetal aneuploidy (with varying probability cut-offs). In this paper we examine how this unique approach to implementing NIPT in Germany is produced by an ethical and policy landscape resulting from a distinctive cultural and historical context with a significant influence on healthcare decision-making. Due in part to the specific legal and regulatory environment, as well as strong objections from various stakeholders, Germany did not implement NIPT as a first-tier screen. However, as Germany does not currently publicly fund as standard other forms of prenatal aneuploidy screening (such as combined first trimester screening), neither can it be implemented as a screen contingent on specific probability cut-offs. We discuss how German policy reflects the echoes of the past shaping approaches to new biotechnologies, and the implications of this unique model for implementing NIPT in a public healthcare system.

The impact of maternal and geographical factors on the uptake of non-invasive prenatal testing: A retrospective cohort study

OBJECTIVES

The objectives of this study were to investigate recent trends in non-invasive prenatal testing (NIPT) utilisation, including factors associated with geographical variation, and to determine whether maternal or regional characteristics are associated with uptake the of NIPT.

METHODS

This retrospective cohort study included pregnant individuals in Ontario with an expected date of delivery from August 1st, 2016 to March 31st, 2020. Modified Poisson regression was used to estimate rate ratios for NIPT use adjusted for maternal and healthcare covariates.

RESULTS

We found substantial variation in NIPT uptake between regions within the province. The highest uptake was found in urban areas, highest quintile of neighbourhood income and education, for those who were ≥40 years of age and had a history of previous aneuploidy, for those with a prenatal care visit in the first trimester, multiple pregnancy, multigravidity and body mass index within the normal range (18.5-24.9 kg/m² ).

CONCLUSION

Our study demonstrated significant regional and maternal differences in NIPT uptake across Ontario. Given the large sample size and diverse population, our study may have implications for other jurisdictions with large, socio-demographically and geographically diverse populations.

Additional value of advanced ultrasonography in pregnancies with two inconclusive cell-free DNA draws

OBJECTIVE

We aimed to evaluate the additional value of advanced fetal anatomical assessment by ultrasound in pregnancies with twice inconclusive noninvasive testing (NIPT) due to low fetal fraction (FF).

METHODS

We performed a multicenter-retrospective study between 2017 and 2020 including 311 pregnancies with twice inconclusive NIPT due to low FF ≤ 1%. Women were offered invasive testing and advanced fetal anatomical assessment at ≤18 weeks' gestation. Ultrasound findings, genetic testing, and pregnancy/postnatal outcomes were evaluated.

RESULTS

Ninety-two/311 (29.6%) women underwent invasive testing. Structural anomalies were diagnosed in 13/311 (4.2%) pregnancies (nine at the first scan and four at follow-up). In 6/13 (46.2%) cases, genetic aberrations were confirmed (one case of Trisomy 13 (detectable by NIPT), two of Triploidy, one of 16q12-deletion, HCN4-mutation and UPD(16) (nondetectable by NIPT). Genetic aberrations were found in 4/298 (1.3%) structurallynormal pregnancies (one 47XYY, two microscopic aberrations, one monogenic disorder found postpartum). Structural anomalies in genetically normal fetuses (2.0%) were not more prevalent compared to the general pregnant population (OR 1.0 [0.4-2.2]).

CONCLUSION

In pregnancies with twice inconclusive NIPT due to low FF, fetal structural anomalies are not more prevalent than in the general obstetric population. The detailed anatomical assessment has the added value to detect phenotypical features suggestive of chromosomal/genetic aberrations and identify pregnancies where advanced genetic testing may be indicated.

Timing of diagnosis of fetal structural abnormalities after the introduction of universal cell-free DNA in the absence of first-trimester anatomical screening

Introduction

Since 2021, first‐trimester anatomical screening (FTAS) is offered in the Netherlands alongside genome‐wide cell‐free DNA (cfDNA). Previously, only second‐trimester anatomical screening (STAS) was offered. This study identifies structural abnormalities amenable to first‐trimester diagnosis detected at/after STAS in the period following cfDNA implementation and preceding FTAS introduction.

Methods

This retrospective cohort includes 547 fetuses referred between 2017 and 2020 because of suspected structural abnormalities before/at/after STAS. Additional prenatal investigations and postnatal follow‐up were searched. Abnormalities were classified into “always”, “sometimes”, and “never” detectable in the first‐trimester based on a previously suggested classification.

Results

Of the 547 pregnancies, 13 (2.6%) received FTAS and 534 (97.6%) received a dating ultrasound and STAS. In 492/534 (92.1%) anomalies were confirmed; 66 (13.4%) belonged to the “always detectable” group in the first trimester, 303 (61.6%) to the “sometimes detectable”, and 123 (25.0%) to the never detectable. Of the “always detectable” anomalies 29/66 (44%) were diagnosed during dating ultrasounds and 37 (56%) during STAS. The rate of termination of pregnancy for anomalies detected during FTAS and at/after STAS was 84.6% (n = 11/13) and 29.3% (n = 144/492) (p < 0.01).

Conclusion

When FTAS is not part of screening paradigms, most fetal anomalies remain undetected until the second trimester or later in pregnancy, including 56% of anomalies “always detectable” in the first trimester.

What's already known about this topic?

About one‐third of all prenatally detectable fetal congenital abnormalities can be diagnosed in the first trimester of pregnancy. Especially major and lethal defects are amenable to early diagnosis.

What does this study add?

This study shows the evident delay in the timing of diagnosis of fetal structural abnormalities when first‐trimester anatomical screening (FTAS) is not routinely offered. The findings of this study strongly support the implementation of a regulated FTAS program in addition to universal screening by cell‐free DNA.

Implementation of non-invasive prenatal testing within a national UK antenatal screening programme: Impact on women's choices

OBJECTIVE

To evaluate the implementation of non-invasive prenatal testing (NIPT) on pregnant women's choices in a national NHS antenatal screening programme for Down's syndrome, Edwards' syndrome and Patau's syndrome.

METHOD

An observational study of all pregnant women with a singleton pregnancy and higher chance (≤1:150) combined or quadruple screening result from 30 April 2018 to 25 September 2020 in Wales, UK. Pregnant women's journey through the pathway was determined including uptake of NIPT, performance of NIPT in a non-research setting and invasive procedures performed.

RESULTS

Of the 1273 women with a higher chance initial screening, 1073 (84%) chose NIPT contingent test, 174 (14%) no further testing and 26 (2%) invasive procedure. There were 1001 (93%) low chance NIPT results; 11 (1%) failed results and 61 (6%) high chance results. Average annual incidence of 27 invasive procedures undertaken compared to 229 pre-NIPT implementation, a nearly ninefold reduction. Down's syndrome annual live birth rate remained unchanged across the implementation period.

DISCUSSION

This study demonstrates that NIPT contingent screening was highly acceptable to women with a resulting reduction in invasive procedures performed.

CONCLUSION

The high uptake of NIPT in NHS antenatal screening pathway conditions should inform planning for other national screening programmes.

Cost of providing cell-free DNA screening for Down syndrome in Finland using different strategies

OBJECTIVES

A financial analysis is carried out to assess costs and benefits of providing cell-free DNA screening in Finland, using different strategies.

METHODS

Three cell-free DNA screening strategies are considered: Primary, all women; Secondary, those with positive Combined test; and Contingent, the 10-30% with the highest Combined test risks. Three costs are estimated: additional cost for 10,000 pregnancies compared with the Combined test; 'marginal' cost of avoiding a Down syndrome birth which occurs in a pregnancy that would have been false-negative using the Combined test; and marginal cost of preventing the iatrogenic loss of a non-Down syndrome birth which occurs in a pregnancy that would have been false-positive.

RESULTS

Primary cell-free DNA will require additional funds of €250,000. The marginal cost per Down syndrome birth avoided is considerably less than the lifetime medical and indirect cost; the marginal cost per unaffected iatrogenic fetal loss prevented is higher than one benefit measure but lower than another. If the ultrasound component of the Combined test is retained, as would be in Finland, the additional funds required rise to €992,000. Secondary cell-free DNA is cost-saving as is a Contingent strategy with 10% selected but whilst when 20-30% costs rise they are much less than for the Primary strategy and are cost-beneficial.

CONCLUSIONS

When considering the place of cell-free DNA screening it is important to make explicit the additional and marginal costs of different screening strategies and the associated benefits. Under most assumptions the balance is favorable for Contingent screening.

Isolated Increased Nuchal Translucency in First Trimester Ultrasound Scan: Diagnostic Yield of Prenatal Microarray and Outcome of Pregnancy

Background: Increased nuchal translucency (NT) is associated with aneuploidy. When the karyotype is normal, fetuses are still at risk for structural anomalies and genetic syndromes. Our study researched the diagnostic yield of prenatal microarray in a cohort of fetuses with isolated increased NT (defined as NT ≥ 3.5 mm) and questioned whether prenatal microarray is a useful tool in determining the adverse outcomes of the pregnancy. Materials and Methods: A prospective study was performed, in which 166 women, pregnant with a fetus with isolated increased NT (ranging from 3.5 to 14.3 mm with a mean of 5.4 mm) were offered karyotyping and subsequent prenatal microarray when karyotype was normal. Additionally, all ongoing pregnancies of fetuses with normal karyotype were followed up with regard to postnatal outcome. The follow-up time after birth was maximally 4 years. Results: Totally, 149 of 166 women opted for prenatal testing. Seventy-seven fetuses showed normal karyotype (52%). Totally, 73 of 77 fetuses with normal karyotype did not show additional anomalies on an early first trimester ultrasound. Totally, 40 of 73 fetuses received prenatal microarray of whom 3 fetuses had an abnormal microarray result: two pathogenic findings (2/40) and one incidental carrier finding. In 73 fetuses with an isolated increased NT, 21 pregnancies showed abnormal postnatal outcome (21/73, 28.8%), 29 had a normal outcome (29/73, 40%), and 23 were lost to follow-up (23/73, 31.5%). Seven out of 73 live-born children showed an adverse outcome (9.6%). Conclusions: Prenatal microarray in fetuses with isolated increased NT had a 5% (2/40) increased diagnostic yield compared to conventional karyotyping. Even with a normal microarray, fetuses with an isolated increased NT had a 28.8% risk of either pregnancy loss or an affected child.

Non-invasive prenatal test uptake in socioeconomically disadvantaged neighborhoods

OBJECTIVE

Non-Invasive Prenatal Testing (NIPT) is increasingly being implemented worldwide. In public health programs, equitable access to healthcare is a fundamental principle which also applies to fetal aneuploidy screening. However, the out-of-pocket costs of NIPT may lead to sociodemographic disparities in uptake of screening. This study assessed whether there is a difference in the uptake of NIPT in socioeconomically disadvantaged neighborhoods compared to all other neighborhoods in the Netherlands, where NIPT is implemented in a national screening program (TRIDENT-2 study).

METHOD

NIPT uptake, postal code and age of 156,562 pregnant women who received pre-test counselling for prenatal screening in 2018 were retrieved from the national prenatal screening database. Postal codes were used as a proxy to categorize neighborhoods as being either socioeconomically disadvantaged or other. The out-of-pocket costs for NIPT were €175.

RESULTS

NIPT uptake in socioeconomically disadvantaged neighborhoods was 20.3% whereas uptake in all other neighborhoods was 47.6% (p < 0.001). The difference in NIPT uptake between socioeconomic disadvantaged neighborhoods and other areas was smaller for the youngest maternal age-group (≤25 years) compared to other age-groups.

CONCLUSION

The variation in uptake suggest underlying disparities in NIPT uptake, which undermines the goals of a national fetal aneuploidy screening program of providing reproductive autonomy and equitable access. This has ethical and policy implications for ensuring fair and responsible implementation of fetal aneuploidy screening.

Routinization of prenatal screening with the non-invasive prenatal test: pregnant women's perspectives

Due to the favorable test characteristics of the non-invasive prenatal test (NIPT) in the screening of fetal aneuploidy, there has been a strong and growing demand for implementation. In the Netherlands, NIPT is offered within a governmentally supported screening program as a first-tier screening test for all pregnant women (TRIDENT-2 study). However, concerns have been raised that the test’s favorable characteristics might lead to uncritical use, also referred to as routinization. This study addresses women’s perspectives on prenatal screening with NIPT by evaluating three aspects related to routinization: informed choice, freedom to choose and (personal and societal) perspectives on Down syndrome. Nationwide, a questionnaire was completed by 751 pregnant women after receiving counseling for prenatal screening. Of the respondents, the majority (75.5%) made an informed choice for prenatal screening as measured by the multidimensional measure of informed choice (MMIC). Education level and religious affiliation were significant predictors of informed choice. The main reason to accept screening was “seeking reassurance” (25.5%), and the main reason to decline was “every child is welcome” (30.6%). The majority of respondents (87.7%) did not perceive societal pressure to test. Differences between test-acceptors and test-decliners in personal and societal perspectives on Down syndrome were found. Our study revealed high rates of informed decision-making and perceived freedom to choose regarding fetal aneuploidy screening, suggesting that there is little reason for concern about routinization of NIPT based on the perspectives of Dutch pregnant women. Our findings highlight the importance of responsible implementation of NIPT within a national screening program.

Uptake of fetal aneuploidy screening after the introduction of the non-invasive prenatal test: A national population-based register study

INTRODUCTION

The introduction of the non-invasive prenatal test (NIPT) has shifted the prenatal screening landscape. Countries are exploring ways to integrate NIPT in their national prenatal screening programs, either as a first- or second-tier test. This study aimed to describe how the uptake of fetal aneuploidy screening changed after the introduction of NIPT as a second-tier and as a first-tier test within the national prenatal screening program of the Netherlands.

MATERIAL AND METHODS

A population-based register study in the Netherlands, recording uptake of fetal aneuploidy screening. Data from all pregnant women choosing to have the first-trimester combined test (FCT) or first-tier NIPT between January 2007 and March 2019 were retrospectively collected using national registration systems. Uptake percentages for fetal aneuploidy screening (FCT and NIPT) were calculated and stratified by region and maternal age. Statistical significance was determined using trend analysis and chi-squared tests.

RESULTS

Between 2007 and 2013 FCT uptake increased from 14.8% to 29.5% (P = .004). In April 2014 NIPT was introduced as a second-tier test for high-risk women after FCT (TRIDENT-1 study). FCT uptake rose from 29.5% in 2013 to 34.2% in 2015 (P < .0001). After the introduction of NIPT as a first-tier test for all women in April 2017 (TRIDENT-2 study), FCT uptake declined significantly from 35.8% in 2016 to 2.6% in 2018 (P < .0001). NIPT uptake increased to 43.4% in 2018. Regionally, NIPT uptake ranged from 31.8% to 67.9%. Total uptake (FCT and NIPT) between 2007 and 2018 increased significantly from 14.8% to 45.9% (P < .0001). However, total uptake stabilized at 46% for both years of TRIDENT-2 (April 2017-March 2019).

CONCLUSIONS

An increase in total fetal aneuploidy screening uptake up to 45.9% was observed after the introduction of NIPT. Uptake appears to have stabilized within a year after introducing first-tier NIPT.