National Screening Committee Performs Consultation on Fetal Anomaly Screening
The following is an edited version of the Right To Life (RTL) public briefing on the consultation carried out recently by the UK National Screening Committee (UKNSC) on introducing a form of non-invasive prenatal testing called cell-free DNA (cfDNA) testing. You can read the full briefing, and the analysis which RTL submitted to the UKNSC, here:
Certain forms of population screenings are performed by the NHS in order to identify healthy people who may be at increased risk of disease or condition, and offer information, further tests, and treatment, in order to reduce associated risks or complications. The UK Government has a National Screening Committee (UKNSC), which advises ministers and the NHS across the UK about all aspects of population screening and supports implementation of screening programmes. This includes Jane Fisher, Director of Antenatal Results and Choices (ARC; an abortion lobby group), as a member.
One of the national screening programmes being run is the ‘Fetal Anomaly Screening Programme’ (FASP), which offers screening for pregnant women to check their unborn baby for fetal anomalies. In this, women are offered a ‘combined test’ (of ultrasound and blood tests) in the first trimester, or a ‘quadruple test’ (so-called because it is a blood test that measures four different elements) in the second trimester, to ascertain risk of Trisomy, also known as Aneuploidy (where an extra copy of a chromosome is present in the cell nuclei, causing developmental abnormalities). The most common forms of these are Trisomy 21 (T21, also known as ‘Down’s Syndrome’), Trisomy 18 (T18, or ‘Edwards’s Syndrome’), and Trisomy 13 (T13, or ‘Patau’s Syndrome’), the numbers corresponding to which of the 23 pairs of human chromosomes has copied.
Currently, on the basis of the risk they are given according to the screening tests mentioned above, women may choose to confirm a diagnosis of fetal disability through Amniocentesis or Chorionic Villus Sampling (CVS). In the former, a needle is passed into the uterus to extract amniotic fluid, and in the latter a tube (inserted through the cervix) or a needle (passed into the uterus) removes tissue from the placenta for testing. The fluid/tissue is then tested for evidence of abnormalities. These are forms of Invasive Prenatal Diagnosis (IPD), and both carry a 0.5-1% risk of causing miscarriage, so only some women choose to go through with either procedure.
Recently, however, a new means of detecting trisomy has been developed called ‘cell-free DNA’ (cfDNA) Testing – also known as Non-Invasive Prenatal Testing (NIPT) – which does not carry either the risk or invasiveness of IPD procedures, but simply involves a blood test in which fetal cell-free DNA can be genetically tested. During pregnancy, a small amount of the baby’s DNA can be found in her mother’s blood, but the majority of the cfDNA in the blood comes from the mother herself. If the baby has trisomy 21, for example, there will be slightly more cfDNA from chromosome 21 than expected in the maternal circulation. Similarly, if the baby has trisomy 18 or trisomy 13 there will be slightly more cfDNA from chromosome 18 or 13 respectively. Analysis of this cfDNA can therefore be used as a screening test for these trisomies.
As a consequence of this development, though its availability is limited in the UK, more women have gone on to receive this test, and have been diagnosed with fetal disability. This has led to a substantial increase in the number of babies aborted due to trisomy. The Department of Health abortion statistics for 2014 reported that 662 abortions were performed on Down’s Syndrome babies (an increase of 12%), with Down’s being the most commonly reported (21%) chromosomal abnormality justifying abortion. This is part of a 34% overall increase in such abortions in the last three years.
Regardless of this, the UKNSC is currently consulting on its recommendation to include in the FASP a systematic population screening that would employ cfDNA testing in order to improve the programme. The UKNSC believe that by offering this to women who are identified as having a risk of 1 in 150 or more of their unborn child suffering from fetal disability, those women would be provided a test that will provide a much better estimate (than the combined or quadruple testings) of the chance that her baby suffers from fetal abnormality. This means that more women can avoid going through with IPD procedures, and the invasiveness and risk they involve.
The UKNSC Consultation:
As part of its regular review cycle of all policies, the UKNSC has commissioned an expert review of its recommendation regarding cfDNA. It has opened a consultation on this expert review, which began on the 30th of July and ends on the 30th of October.
The expert review takes into account a pilot study by RAPID (Reliable Accurate Prenatal non-Invasive Diagnosis), which is a five-year UK national programme funded by the National Institute for Health Research (NIHR). It also takes into account a systematic review that the UKNSC commissioned themselves. Based on these findings, the UKNSC has made recommendations on FASP use of cfDNA (A document summarising these, as well as the systematic review and a summary of the pilot study, are available through the consultation website).
The RAPID study enquires as to the ‘optimal’ method of utilising NIPT in the FASP. The study looked at women recruited for the study from four NHS centres between November 2013 and June 2015, presenting results of the women who had been recruited earliest in the study (in the first seven months) to maximise data about pregnancy outcomes.
Participating centres offered NIPT to all women who, having gone through the combined or quadruple test, were given a screening risk of T21 of greater than 1:1000. Those women with a risk of greater than 1:150 were offered NIPT or invasive prenatal diagnosis (IPD). Women at some of the NHS centres were also given a risk for T18 and T13, and offered further testing if their risk was greater than 1:1000. Altogether, 1,164 women who had a risk of between 1:2 and 1:1000 for the main three trisomies took up NIPT.
The study found that:
- NIPT was very reliable in detecting T21, with a 100% detection rate and no false negatives. Only 8 (0.7%) of the NIPT tests required re-taking due to failed or inconclusive results.
- Offering NIPT led to more women in the 1:150 risk group opting for further testing after the combined and quadruple test (60% before the study, 95% after), with 77% opting for NIPT. This was taken to be the removal of a barrier to further testing that IPDs represent for many women due to the risk and invasiveness of such procedures.
- As more women opted for NIPT, fewer women opted for IPD. Whilst after the combined/quadruple test alone, there were over 10 invasive tests are carried out for each Down’s pregnancy detected, when NIPT was offered there were only 2.8.
The conclusions of the RAPID study were that implementing the use of NIPT in the FASP, but limiting this to those women with a risk of 1:150, would increase the number of Down’s cases detected slightly, dramatically reduce the number of invasive tests and procedure related miscarriages, and marginally lower the estimated costs (by £337,000). Offering it to more women (those with lower risks of 1:500 to 1:1000) would increase the number of DS cases detected, and maintain a significant reduction in IPDs and procedure related miscarriages, but increase the overall costs by millions of pounds (£3,365,000-£7,809,000).
By contrast, the UKNSC-commissioned study constituted a systematic review of literature dealing with the efficacy of cfDNA testing (following combined testing) in detecting trisomy, and its cost. Unlike the RAPID study, their combination of 41 different research studies (conducted in order to achieve an overall estimate of test accuracy) found that cfDNA testing was sufficiently capable of yielding inaccurate results that it should not be considered as a diagnostic test for trisomies. Instead, it recommends that pregnant women with positive results from cfDNA should additionally be offered an IPD to ensure a conclusive diagnosis.
The UKNSC review goes on construct an economic model to compare three options of whether or how the NHS could use cfDNA in the FASP:
- Keep the current FASP: Offer the combined test, and then IDP to those pregnant women given a screening trisomy risk of 1:150.
- Add the cfDNA test to the FASP after the combined test: Offer the combined test, offer the cfDNA test to women given a consequent risk greater than 1:150, and offer IDP to those women who test positive to the cfDNA. This option was projected to result in similar numbers of trisomies detected, with 43 fewer miscarriages of healthy pregnancies because of many fewer women choosing to have invasive tests than currently, and to cost approximately the same as the current system.
- Replace the combined test with cfDNA test: Offer the cfDNA test as an initial test, replacing the combined test, then offer IDP to those women who test positive. This was projected to result in more invasive tests than the second option, and to cost an extra £105 million to the NHS.
The same three concerns are present both in the UK NSC Review and the RAPID study:
- Improved detection of trisomy cases
- Reduction of invasive testing
- Overall screening programme costs
The UKNSC review is more pessimistic about the efficacy of cfDNA in detecting trisomy, due to the pooling of data from the 41 studies it looked at regarding Sensitivity (that is, the rate of false positives) and Specificity (that is, the rate of false negatives. Applying these test accuracy values to a high risk population the review found that the positive predictive values are 91% (T21), 84% (T18), and 87% (T13), respectively. This means, for example, that if 100 women were given a positive result that their baby had a replicated T21 chromosome, 91 of these would actually have Down’s syndrome. Since this is sufficiently lower than a 100% success rate, the review recommends that women be offered IPD in addition to cfDNA as a means of giving final diagnosis (this seems odd, given the comparable reliability of CVS).
The two elements of the expert review come to slightly differing conclusions about the effects of adding an offer of the cfDNA test to the FASP as an option to women given a 1:150 risk of trisomy after the combined test:
- Detections of Trisomy – The RAPID study projected 102 more detections of T21, whereas the UKNSC review projected 20.2 more T21 detections (as well as statistically less than 1 more detection of T18, and T13 respectively), with 1.056 trisomies detected overall (an increase of 24).
- IPD Procedures – The RAPID study projected 4,870, and the UKNSC review projected 6,476 fewer (t0 3,040 and 1,434 respectively).
- IPD-Related Miscarriages – The RAPID study projected 25 fewer, and the UKNSC review 43 fewer (though this latter figure is of apparently specifically ‘healthy’ pregnancies), to 21 and 3 miscarriages a year respectively.
- Cost to the NHS – The RAPID study projected £337,000 less cost, and the UKNSC a higher cost of £130,000. This would mean a total cost of £14,593,000 and £15,060,000 respectively.
These are only slightly disparate projections, and thus they allow for the same conclusion: that cfDNA testing should be offered to women through the FASP who have a 1:150 risk of trisomy. They both predict that the greater certainty of trisomy detections given by cfDNA will lead many more women to eschew IPDs, and for this to result in dozens fewer consequent miscarriages.
As a consequence of the expert review, consisting of the systematic review and the RAPID pilot study, the UKNSC is recommending:
- That cfDNA testing be offered to women whom, after combined testing, receive a trisomy risk score (for either T21, T18, or T13) equal to or greater than 1:150.
- That women be advised that cfDNA tests are not diagnostic and that for a definitive diagnosis they must undergo IPD.
The UKNSC’s basis for this recommendation was down to a concern that at the 1:150 risk level the number of women with false positive results that are offered an invasive test is markedly reduced as compared to those at lower risk, and that providing cfDNA to the resultant number of women at that risk level would mimimally affect the cost of the FASP, minimally change and disrupt its pathway, be least affected by the current capacity of cfDNA testing in the UK, allow uncertainties in the implementation of cfDNA (to do with sensitivity and specificity rates, patient uptake, and turnaround) to be explored and learned from, and because it would not lower the number of trisomy pregnancies detected.
As well as consulting on its recommendations, the UKNSC has also consulted on its decision not to replace combined testing as the primary screening test, which they decided not to recommend on the basis of the cost to the NHS, despite predicting that such a change would lead to approximately 289 more babies with trisomies being detected (albeit with 5,711 fewer IPDs being performed, as opposed to the 6,476 fewer that their recommendation is projected to achieve, according to the UKNSC review).
From the right-to-life movement’s standpoint, whilst the extension of the use of cfDNA (if the studies the UKNSC cites are right) could reduce the number of miscarriages that occur due to IDP procedures, it would also certainly increase the number of abortions that are undertaken due to disability.
If the findings of the RAPID study are accurate, and 102 more Down’s babies are detected every year, then assuming similar annual figures to the latest reported by the National Down Syndrome Cytogenetic Register (NDSCR) for England and Wales – that 91% of babies who are prenatally diagnosed with Down’s Syndrome are aborted – this would result in 93 more babies being aborted for disability every year. That is as opposed to 25 fewer miscarriages due to IDP. If in the future cfDNA were to replace combined and quadruple testing as the primary screening test, then 263 more babies would be aborted every year, and there would be 3 extra IPD-related miscarriages. Whilst we should not be utilitarian in our approach to human life, we should be concerned of the effect these developments will have on human lives.
Indeed, given the problem of this abuse, it should be asked what effect the introduction of cfDNA in detecting trisomies will have on the FASP’s ability to expand to detecting other groups? It would seem that normalising the practice, and ingraining it as part of the screening system, and with a lowering of overall costs, would help enable such expansion. Indeed, this could lead to further abuses – more babies with chromosomal abnormalities could be identified and aborted, and since cfDNA allows for a test of fetal sex, this could thus help to enable sex-selective abortions. In the future, this could allow for the testing of the entire human genome, and the targeting of unborn children for abortion based on a range of illicitly considered characteristics. How such abuses would be obviated is an important concern that the Government needs to address before allowing the implementation of this technology.
Additionally problematic is the approach that the UKNSC consultation takes towards Down’s Syndrome babies, and other unborn children with trisomy. The goal that the UKNSC appears to be trying to achieve is the lowering of the number of miscarried ‘healthy’ babies, but without any evident concern for the babies who are detected as having trisomy as to whether they are miscarried. The fact that the UKNSC Consultation Document included he figure of ‘Cost per trisomy detected’, this suggests that the UKNSC reduces each trisomy baby to being merely a drain on NHS resources.
Indeed, given the number of these babies who would be aborted, to make a change to the inclusion of cfDNA before many of the practical improvements to how parents who go through a diagnosis of fetal disability can be offered help and education to bring up a disabled child (such as were identified in the Parliamentary Inquiry on Abortion and Disability in 2011), would be deeply imprudent and harmful. The assumption commonly made that women whose unborn child is disabled will want an abortion, an assumption that has led to many women being led into a decision they have deeply regretted, particularly needs to be addressed.
The approach of the consultation would appear to violate the UK Government’s obligations as a signatory to the U.N. Convention on the Rights of Persons with Disabilities (CRPD) (the implications of this for fetal screening are accounted here). Screening programmes that, as in this case, target specific groups of disabled children in utero, send the message that such persons are not welcome in society. This brands such people as a burden, particularly on the health services and society more largely, whilst passing over their intrinsic human value and place in the community.
To even implicitly wish to ‘screen’ out disabled people, and avoid their existence altogether, runs counter to respect for human diversity and human rights principles generally, including respect for human life as reflected in the U.N. Convention on the Rights of the Child (UNCRC). This provides that States Parties “shall ensure to the maximum extent possible the survival and development of the child”, and mentions the child as requiring protection “before as well as after birth”.
It is incumbent upon State signatories of the Convention to incorporate into CPRD policy reviews (pursuant to Article 4) – including its policies on disability selective antenatal screening – a social model of disability assessment, including undertaking an analysis of the socio-contextual conditions within which such policies are implemented and their consequent effects.
Crucially, the CRPD also requires consultation with people with Down’s Syndrome on a programme such as this that affects them (and profoundly negatively). Yet only one organisation advocating for people with Down’s is represented on the list of stakeholders on the UKNSC consultation page. The apparent assumption made in the consultation that saving non-trisomy ‘healthy’ pregnancies is a benefit, with no interest shown in reducing harm to trisomy pregnancies, is a bias based on genetic difference that constitutes a form of unjust discrimination prohibited under the CRPD. The UKNSC is under an ethical obligation to reduce harm to both trisomy and non-trisomy unborn children concurrently.
Since the cfDNA proposal would lead overall to a worsening situation for disabled unborn children, and violates the UK’s obligations as a signatory of the CRPD, RTL has recommended the following in response to the UKNSC consultation:
- That the UKNSC at least delay the implementation of cfDNA procedures, to avoid the harms they will accrue.
- That such harms be avoided by reforms being made to medical practice so that parents who are given a diagnosis of fetal disability can be offered the requisite help to take care of a child with Trisomy, in keeping with the UK’s commitment under the CRPD to render appropriate assistance to prospective parents.
- That the UKNSC observe its obligations to due process and right to full information by extending the consultation, publicising it more widely, and creating easier access both to an understanding of the expert review and to individuals making a submission.
- That the UKNSC and all UK Governmental bodies review their approach to fetal disability (including screening) and align it with the CRPD.
If used properly, cfDNA testing could help prepare parents who have a disabled child to take care of their new baby, and to allow help to be provided to them in this role. Currently, however, without the culture and practices in place to enable this to happen, the implementation of any NIPT technique would worsen the current situation for both unborn children and their parents, and contribute to the pervasive perception that disabled lives are worth less than others, as well as other invidious and lethal forms of discrimination. Until our health system is fully committed to enabling, rather than disabling and thereby failing, patients who receive diagnoses of fetal disability, a potential good will become an actual harm. For that reason, it must be currently opposed by all those who support the equal dignity and rights of all human beings.