Prenatal Diagnosis

First-trimester screening: dealing with the fall-out

Authors


Abstract

The articles collected together in this issue describe first-trimester screening for a variety of complications. With the advance of both technology and research, early pregnancy screening is becoming ever more sophisticated and complex. While there are clear benefits to most women receiving early reassurance that their baby is developing as expected, there is no evidence to suggest that an earlier prenatal diagnosis has less long-term emotional impact than at later gestations. The poignancy of ultrasound images for many parents means that it can be especially difficult to manage the anxiety when an ultrasound marker is highlighted as potential cause for concern. They can then face a journey of anxiety-laden uncertainty, which can extend through much of the pregnancy, and even beyond. Professionals involved in screening need to recognise and acknowledge such adverse side-effects and develop the skills necessary to help parents understand and cope with the uncertainties inherent in the process. Copyright © 2011 John Wiley & Sons, Ltd.

INTRODUCTION

Antenatal results and choices (ARC) is the only UK charity providing non-directive, independent information and support to parents throughout prenatal screening and testing and its aftermath (www.arc-uk.org). ARC has maintained a close and collaborative working relationship with professionals involved in the field, recognising that giving worrying news to parents during prenatal screening is a challenging area of practice. When we were established as a charity in 1988, 90% of calls to our National Helpline were either from parents struggling after undergoing a termination for fetal abnormality or trying to make sense of a prenatal diagnosis. The diagnoses were most commonly made following amniocentesis or what was then termed ‘the 20 week scan’. Now, 40% of our helpline calls and e-mail queries are from parents wanting help in understanding the implications of Down syndrome screening test results. On average, we hear from at least five individuals every day who are trying to make sense of the statistical chance they have been given or are particularly concerned about the significance of a particular marker. At the time of writing, every woman having prenatal care in England and Wales is offered a screening test for Down syndrome through their NHS hospital and most in England can access combined screening in the first trimester (UK National Screening Committee, 2008). Intuitively, we may have predicted that ARC would have seen a reduction in ‘screening result anxiety’ calls with more widespread availability of combined testing, which is more sensitive with fewer women categorised as ‘screen positive’ (Nicolaides, 2011). However, while the level of calls has not changed, the content of the calls has changed. We still take a high proportion of calls from women or partners wanting help in making sense of the statistical information that has been applied to their unborn baby. They are most often wrestling with how to interpret the numbers as they try to decide whether to have invasive diagnostic testing. But we have seen a definite increase in calls from parents who have been made especially anxious by a component of the screening test and become focused on the implications of a particular marker. While most of these calls concern worries about raised nuchal translucency (NT), recently we have been contacted more frequently about other first-trimester ultrasound markers.

Maternal anxiety caused by the detection of ultrasound markers is not new (Watson et al., 2002), but analysis of our helpline log over the last 2 years shows a 50% rise in contact from women who have had extended first-trimester screening. The sensitivity and specificity of the standard first trimester combined test is improved by adding a number of markers such as nasal bone, fetal heart rate, blood flow in the ductus venosus and tricuspid valve and facial angle (Nicolaides, 2011). We at ARC are fully supportive of this pioneering work and its goal to provide the highest possible quality first-trimester screening. That said we find ourselves dealing with the ‘fall-out’ on our helpline, that is, the more complex the screening process, the more potential there is for confusion, anxiety and sometimes distress. Here, I will explore some of the less welcome side-effects from advances in first-trimester screening and suggest how we might mitigate against potential harms. Throughout this article, I refer to ‘parents and baby’ because that is how most people conceptualise a wanted pregnancy. So, when a first-trimester diagnosis is made, parents grieve the loss of a healthy baby, not a developing fetus.

It has to be acknowledged that much of the parental feedback that informs this article comes from women and partners who have chosen to access ARC's support services, which is only a small proportion of the entire screened population. What adds to the validity of this input is that it has generally been corroborated by the extensive contact we have with health professionals in the field. We deliver a well-established programme of study days for professionals on communication skills and supporting decision making in the context of prenatal testing, which has been taken up by thousands of practitioners across the UK.

Do women want first-trimester screening?

We know that the majority of women in England choose to have screening for Down syndrome (NHS Fetal Anomaly Programme Report, 2008/2009). There are no accurate data to tell us how many women in the UK opt for screening in the first trimester as it is unavailable in some regions (http://fetalanomaly.screening.nhs.uk/ localscreening) and we do not know exactly how many women seek testing in the independent sector. However, it is interesting that NHS trusts who have implemented it report a rise in uptake from levels when second trimester serum screening was the only option (Moonlight, 2009). Furthermore, ARC receives calls weekly from women who are keen to have combined screening but are in a region that only offers second trimester tests. Most women report that the earlier reassurance combined screening can provide is something they value. They are also attracted by the ultrasound components of the test as this affords the opportunity to see their baby and to be reassured that it appears to be developing as expected. Once given a reassuring result and having negotiated the first trimester without miscarrying, they are then happy to share news of the pregnancy with others.

Another draw to first trimester testing for some women is the possibility of having a surgical termination of pregnancy should a positive diagnosis be made (either at the scan or through a subsequent CVS). In the abstract, this can seem a less traumatic way of ending a wanted pregnancy. There are also women from particular faith groups for whom termination is only an option if it can be carried out before a certain gestation.

Research and ARC's experience as a support organisation do not suggest that the long-term emotional impact is lessened according to abortion method or timing (Statham et al., 2000). However, despite the roll-out of first-trimester screening and diagnostic services in England, with the premise of enabling earlier ‘reproductive choices’, the majority of NHS hospitals have a cut-off for the provision of surgical termination procedures of 13 weeks. By the time, most women have their chorionic villus sampling (CVS) results they miss this deadline and are unexpectedly faced with a medical managed termination.

While women may want earlier screening, when performed in the first trimester it gives them less time to process pre-test information. All women in England will be given written pre-test information about prenatal screening and the opportunity to discuss it with a midwife. However, even when their first consultation (or ‘booking appointment’) with a midwife is scheduled before first trimester testing, screening is one of a multitude of topics to be covered. There is rarely time to go into detail about all the components of screening programmes and possible sources of anxiety. If the process is to become more complex we will need to consider how we are going to address this when pre-test counselling is already pressured.

A further challenge for professionals is that many women do not want or feel able to fully engage with the potential negative consequences of embarking on screening. From a small-scale audit ARC carried out in four NHS hospitals providing combined screening the qualitative data suggested that few women actively ‘opted in’ and were more likely to view it as routine (ARC, in press). As it was early in pregnancy, at a stage where it still felt quite tentative, they were reluctant to give too much thought to potential abnormalities.

‘I didn't mind that it seemed to be done as a matter of routine—it was reassuring in a way.’

‘I wanted to see the baby; I wasn't thinking about Down syndrome specifically.’

What this tells us is that while pre-test information and counselling is important, it is unlikely we will ever ensure that every woman embarking on screening is fully aware of all potential consequences. It is therefore vital that care is carefully co-ordinated when women are confronted with a worrying outcome and that all staff on the screening pathway are appropriately trained to deal with these circumstances.

The power of the ultrasound image

There is huge emotional resonance for parents when they see their baby on scan. The quality of ultrasound imaging has improved dramatically in ARC's lifetime. Parents no longer need help interpreting scan pictures—they see a clearly recognisable baby on screen. Testimony to this is the lucrative industry of ‘bonding’ scans and souvenir three-dimensional scan DVD that exploits the emotive power of ultrasound images.

‘The sight of your baby on the screen is so emotional with the realisation that you have created life. Everything is so real once you see your baby.’

(Quote taken from letter to ARC written by a father whose baby had been diagnosed with spina bifida).

The excitement of seeing their baby on scan intensifies the impact of an unexpected finding, whether it be an obvious structural abnormality or a marker that may indicate an underlying problem or indeed be an incidental finding. It can be worrying to receive a report printout after serum screening with information that a particular hormone level is higher or lower than average, but it is instantly significant when concerns are highlighted on the scan image showing the baby. A woman is unlikely to have physically felt movement, but sees her baby moving on the screen. Equally, being assured that everything ‘looks’ fine can lead some parents to expectations of a guaranteed healthy baby and make a subsequent diagnosis all the more difficult to assimilate.

Nuchal translucency—anxiety raised by the millimetre

An increased NT measurement between 11 and 14 weeks is a well-established marker for potential chromosomal, cardiac and genetic abnormalities (Avgidou et al., 2005; Bahado-Singh et al., 2005; Clur et al., 2009; Bilardo et al., 2010). Its potential clinical significance should not blind us to the fact that news about a raised NT is particularly difficult for parents to deal with and, whatever the outcome, changes the nature of their pregnancy. Suddenly, they find themselves on a roller-coaster ride of further testing and worry about potential anomalies that go way beyond Down syndrome (Bilardo et al., 2010). If the combined risk is great enough, invasive testing, usually by CVS, will be offered and then standard practice in most units dictates that if the NT is greater than 3.5 mm a detailed cardiac scan should be offered (Clur et al., 2009). Even if nothing is detected through further investigations, many parents have difficulty managing the residual fear that their baby may have an underlying genetic disorder for which there is no prenatal testing available (Bilardo et al., 2010). Some women find it almost impossible to contain the anxiety raised by a high NT measurement and contact us to discuss the option of termination (Bilardo et al., 2007).

We at ARC would never advocate falsely reassuring parents in these circumstances as they need accurate information on possible outcomes, but we have observed that the degree of distress is often commensurate with how the finding and its significance has been communicated. There are parents who come away with the impression that the prognosis for their baby with the 3.9 mm NT is inevitably bleak and decide to end the pregnancy rather than embark on what feels like an impossible journey of further testing and potentially the news later down the line of a serious problem. This is, of course, their prerogative but we would hope that such a decision is not made because such parents did not feel that they had recourse to support in carrying the weight of uncertainty set in motion by the increased NT measurement.

From our 20 years' experience of training health professionals, we know just how difficult it is to give information to parents which is fraught with uncertainty. Professionals and parents alike want to have clarity and as much prognostic information as possible. Our study days explore the very real challenges for clinicians and parents in situations such as a 3.9 mm NT measurement and the range of outcomes that may ensue. What parents tell us they value is that their health professionals explicitly acknowledge the anxiety that accompanies such findings. They find it helpful to be able to ‘offload’ their concerns to a suitably trained midwife and have access to specialised independent support such as that provided by ARC.

Recent advances in first-trimester Down syndrome screening

It is not just NT that engenders high levels of anxiety:

‘My consultant said that overall my risk is low but he couldn't see a nasal bone and that this is quite a strong marker for Down. I've read that only 1–2% of unaffected babies have no nasal bone. So does that mean I have a 98% chance of my baby having Down syndrome?’ (ARC Helpline).

Over the last 3 years we at ARC have become accustomed to almost daily conversations on our helpline with women and their partners in the first trimester about absent, hypoplastic or non-visualised nasal bones. We hear from callers, similar to the example above, who are disturbed by the news that their baby's nasal bone was not seen at a first trimester scan and are unable to trust their combined ‘low-risk’ result. Frantic searches on the Internet fuel the anxiety further, as statistical information appears to substantiate their fears that the absence of this particular marker means they should prepare for the worst. We have had ongoing e-mail contact extending over several weeks from women who pay for extra scans in the hope that someone will be able to verify that a nasal bone is present. Some women come to us needing to offload the high levels of stress that have built up in the 8 weeks or more before their mid-pregnancy anomaly scan. They try to steel themselves for an amniocentesis should the nasal bone still be declared absent.

In our experience, many women suffer a level of distress that is wholly disproportionate to the predictive power of an absent or hypoplastic fetal nasal bone in isolation. However, compelling the data may be as to its value as a marker (Sonek et al., 2006) it requires a highly skilled practitioner to visualise it accurately. Furthermore, its size, presence or absence can be influenced by factors such as parents' own facial features or ethnicity (Collado et al., 2005). It is hard for parents to interpret their ‘low-risk’ combined screening result when the fact that the nasal bone is not visualised is highlighted.

In third position among first-trimester ultrasound marker worries heard on the ARC helpline is the news that the scan has shown reverse flow in the ductus venosus or tricuspid regurgitation. Although the NT and the nasal bone can be relatively straightforward markers to explain to parents, markers involving fetal blood flow are more complex and can be more challenging for professionals to communicate effectively. Rather than recognisable ultrasound images, assessment involves Doppler ultrasound with its unnervingly bright colours and strange wave patterns. Both markers relate to the fetal heart, which immediately ups the scale of worry as parents question whether the findings might indicate a problem with this most symbolic of organs. Ideally, women may be offered an expert cardiac scan as soon as possible which will most often help allay these fears. Some have to wait 2–3 weeks, but others will face a stressful 2-month wait for their anomaly scan. Once again, a trawl of the Internet in this interim period can exacerbate worry and give parents a misleading picture of the actual risks they face.

As regards the ductus venosus, we have found ourselves explaining to helpline callers that, unlike in other screening contexts, the use of the word ‘positive’ on their scan report (a-wave positive) is actually reassuring news.

A note on twin pregnancies

There is no doubt that first-trimester screening has benefits in twin pregnancies. If nothing else it should enable early establishment of chorionicity and planned specialist care if necessary (Wan et al., 2011). On a less positive note, it is also the case that screening in twin pregnancies is likely to be less accurate than in singletons (Wright et al., 2011). This has implications when parents will use the results to make decisions about invasive procedures which carry higher risks when performed in twin pregnancies.

For parents given the news that one of the twins has an abnormality, some will face painful decisions about selective reduction. If a diagnosis is made before 14 weeks they will feel under pressure to make a quick decision and have the procedure at what many clinicians deem the optimal time to maximise the chances of the unaffected twin. As the risks of selective reduction rise with gestational weeks, parents who do not have an early reduction may face the prospect of going almost to term and having selective feticide at 32 weeks or beyond. This is hugely demanding emotionally and will require the provision of specialised support to deal with the complexity of welcoming one child to the world and at the same time grieving for the other (Bryan, 2005).

CONCLUSION

We at ARC will welcome the day when all women can be offered a quality assured first-trimester screening programme which will help them make informed choices about the management of their pregnancy. We know that the vast majority of women who have first-trimester screening will be reassured and have a positive view of the experience, including those who have a more comprehensive package. Glowing accounts of screening at world leading centres abound on the message boards of popular parent networking websites, such as mumsnet.com and babycentre.co.uk. It is unlikely that the level of technical expertise reported in the articles in this issue will be replicated in all hospital settings in the foreseeable future, but technology and research will continue to advance and expand the capabilities and the sophistication of first-trimester screening. Let us just be cautious that small increments in sensitivity do not result in excessive increases in anxiety for too many women, which in some cases can last for weeks or even throughout and beyond the pregnancy.

More comprehensive first-trimester screening is inevitably going to be the source of devastating news for the small number of parents who are alerted to an affected pregnancy. We must also be mindful that it presents the danger of generating enduring anxiety in another category of parents. Those whose baby is found to have a particular marker that is outside the normal range or ‘abnormal’ will need this carefully explained. Such findings might not prompt the offer of immediate diagnostic testing, but we should not underestimate the difficulty for parents who learn that something is not as expected at an early stage in pregnancy and are then asked to wait some weeks before further investigations may or may not be able to give a clearer prognosis. Professionals delivering screening must of course have the necessary technical competencies, but explaining complex information and presenting uncertain outcomes also requires high quality communication skills. ARC would recommend that all professionals engaged in prenatal screening have access to training that can help develop their confidence and competence in handling uncertainty and managing parental anxiety.

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