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I Informed Choices
There is a strong consensus in ethical guidelines published in Europe, the US and elsewhere that health professionals providing prenatal testing services should give women and their partners the information and support they need to make autonomous, informed decisions [RCP, 1989; Andrews et al., 1994; Baumiller et al., 1995]. As well as health professionals and policy makers, users of prenatal services also place a high value on services that allow them to make an informed choice about prenatal tests [Dodds and Newburn, 1997; Carroll et al., 2000]. Such an emphasis reflects a commitment to distance the practice of current genetics from past abuses, particularly those in Nazi Germany [Duster, 1990; Muller-Hill, 1988]. It also reflects a growing recognition that it is unethical for individuals not to be informed of the consequences of medical interventions, particularly ones in which risk information is being provided (Kenen, 1996). There is also a belief that an informed choice, compared with an uninformed one, is associated with better patient outcomes. Few studies, however, have examined the psychological consequences of informed choices in relation to prenatal or other types of tests. In other areas of health care, however, there is good evidence showing that psychological preparation for stressful medical procedures is associated with better psychological and clinical outcomes [Johnston and Vogele, 1993]. How much benefit informed choices, as opposed to choices that are uninformed, confer in those declining or those undergoing prenatal testing, remains to be determined. Attempts to quantify such benefits may provide greater incentives than currently exist to provide services that facilitate informed choices.

Despite a consensus on the importance of informed choice there are few definitions and even fewer measures. There is however an emerging consensus that an informed choice or decision has two core characteristics: it is based on relevant, good quality information, and reflects the decision-maker's values [Marteau et al., in press]. Most research to date has focused upon information provision and understanding as indicators of the extent to which decisions are informed. Very little research has focused on women's values, to determine first, the extent to which their decisions reflect their values, and second, how services are best organized to allow choices to reflect values.

II Informing women: what do women want?
High quality information about the nature and risks of the tests offered , given personally by health professionals as early as possible in prenatal care to allow time for reflection and informed decision making. Research suggests that this does not happen in practice. [Dodds and Newburn, 1997; Carroll et al., 2000, Marteau et al., 1988; Smith et al., 1994(a); Chilaka et al., 2001]. A professional consensus is evident in several sets of guidelines concerning the information that women need when offered prenatal testing [American College of Obstetricians and Gynecologists, 1987; Joint Working Party of the Royal College of Obstetricians and Gynaecologists, and the Royal College of Paediatrics and Child Health, 1997]. These include (a) information on the condition for which testing is being offered, (b) the characteristics of the test and (c) the implications of possible test results.

(a) Information about the condition
The information provided about the conditions for which testing is provided tends to be brief [Murray et al, 2001; Marteau, Slack, Kidd & Shaw, 1992]. In an overview of information presented about prenatally diagnosed conditions, Asch (1999) concluded that the information provided was too negative, given the results of surveys showing that disability most often does not lead to an unsatisfying life. Information provided on conditions is generally more negative when provided to those considering prenatal testing than to those considering testing at other times or to parents with an affected child [Lippman and Wilfond, 1992; Loeben et al., 1998]. This raises the question of what comprises a balanced picture of life with a disability. Those with a disability perceive the conditions as less serious than those without a disability [Marteau and Johnston, 1986]. Thus, adults with a condition are less likely to endorse termination of pregnancies affected by their condition than are parents with affected children [Conway et al., 1994; Henneman et al., 2001]. Whatever the origins of the differences, their existence indicates the importance of eliciting the views of many groups in order to obtain as full a view as possible of how to present conditions to prospective parents. The need to assess the impact upon decision-making of different views is suggested by the counter-intuitive results of an analogue study, comparing the effects of different pictures of children with Down syndrome [Figueiras et al., 1999]. A picture portraying a positive image of a child with Down syndrome had a similar impact to a negative image: both resulted in higher concerns about having a child with the condition, compared with the level of concern generated in those given no picture. Prospective studies are needed to compare outcomes for parents making different decisions based on different types and amounts of information about conditions.

(b) characteristics of the test
Most people have unrealistic expectations of screening tests, overestimating the number of cases they can detect, and underestimating the number of people recalled who are subsequently shown to have no problems [Cockburn et al., 1995]. Few studies have compared the different ways in which such information can be presented. There is good evidence from other areas to show that quantifying uncertainty using frequencies (eg 10 in every 1000 women) rather than numerical probabilities (eg 1 in 100 chance) leads to greater understanding [Gigerenzer and Hoffrage, 1995; Hoffrage and Gigerenzer, 1998]. Two studies in the area of prenatal testing evaluating women's understanding of the risks following screening for Down syndrome show better understanding when risks are presented using numbers rather than words [Marteau et al., 2000] and, when numbers are presented, using frequencies rather than probabilities [Grimes and Snively, 1999]. More research of this type is needed given the centrality of risk perceptions to women's decision making about prenatal tests [Markens et al., 1999].

(c) implications of testing
To make an informed choice about prenatal tests, women need information on the outcomes of testing. These include the possibility of a miscarriage following invasive diagnostic tests as well as the options available following the diagnosis of a fetal anomaly. For diagnostic tests, it is important to convey the risks inherent in such procedures. The possibility of a miscarriage can be presented in numerous ways. Results from a recent analogue study suggest that the framing of such risks might affect women's decisions [Shiloh et al., in press]. Further work is needed to ascertain first the extent to which such variations influence actual decisions, and second the ways of framing the information result in optimal levels of informed choice. The options following the diagnosis of a fetal anomaly include termination of the affected pregnancy, as well as continuing with the pregnancy, while preparing for the birth of a child with special needs. Information on the first option as opposed to the second option is more often given, although it is not always provided either in writing or orally [Loeben et al., 1998; Marteau et al., 1994; Bernhardt et al., 1998]. Information is less often given about the impact of living with a child with a disability, including the educational and medical support that is available, and the likely impact of such a choice upon family life. Evidence-based information that prospective parents would find useful is most likely that which is gathered from multiple sources [Holmes-Rovner et al., 2001].

III Media for providing information
Information can be presented using one or more media. Most often it is presented in writing and orally, by health professionals providing prenatal care.

(a) written information
Written information about prenatal tests varies widely in length, areas covered and the ways in which the information is framed. For example, Murray et al (2001) examined the extent to which 81 leaflets used in British screening programs met criteria for good quality leaflets. Overall, the quality of the leaflets was judged to be poor. In terms of factual content, only 11 (14%) included information on all recommended eight items recommended by a professional body [RCOG, 1993]. In a quantitative analysis of 28 leaflets produced for US and UK cystic fibrosis carrier testing screening programs, the amount of information provided ranged from 1 to 37 statements (median=6.5), with most statements being classified as neutral and only a minority conveying a positive or negative image of the condition [Loeben et al, 1998]. Positive statements were less common in UK leaflets, commercially produced leaflets and leaflets describing prenatal carrier testing. The impact of such variations upon uptake of tests has not been described. Evidence to suggest that the impact of leaflets is likely to be quite small, compared with the impact of orally presented information or the way services are delivered, comes from a study in which uptake of prenatal screening in 14 hospitals using the same leaflet was more varied than uptake across nine hospitals using different leaflets [Dormandy et al., in press].

(b) orally presented information
Observational studies of health professionals presenting prenatal tests to women attest to the complexities facing health professionals in communicating with women with diverse needs (Rapp, 1988). Interview studies with women suggest that their attitudes towards undergoing tests are shaped in various ways by these health professionals (Press & Browner, 1997).

Tape-recordings of consultations both in the US and the UK in which prenatal screening tests are being presented reveal that the information provided is insufficient for informed decision-making, providing too little information, which is occasionally misleading or inaccurate [Marteau et al., 1992; Bernhardt et al., 1998]. Several factors could explain this. First, health professionals themselves sometimes don't have sufficient knowledge about the tests [Smith et al., 1994(b); Sadler, 1997]. Second, they can lack even basic counseling skills needed to present information in a way that makes it understandable [Smith et al., 1995]. Third, they may lack the time to present the information [Green, 1994]. More generally, the lack of high quality information provided at many centers may reflect negative attitudes towards providing such information [Green, 1994; Khalid et al., 1994]. Understanding more about such attitudes could prove an important step in increasing the quality of information women receive from their health care providers.

Brief training can improve both health professionals' knowledge and their skills at providing information [Smith et al., 1995]. However, participation in this trial was low, with only 69% of midwives and obstetricians approached to participate in the study accepting, with those accepting holding more positive attitudes towards such training than those who declined. Of those who did accept, only 40% completed the training and evaluation. Of more concern is the fact that those who completed the trial, compared with those who dropped out, had better baseline communication skills and provided more information to patients, suggesting that those most in need of training are those less likely to avail themselves of it [Michie and Marteau, 1999]. This suggests the need for mandatory training programs. In addition, such training should form an integral part of medical and nursing training, as well as the training of genetic counselors.

(c) other media for communicating information
Two studies have evaluated the effectiveness of videos in providing information. One found an increase in knowledge [Hewison et al., 2001]; the other did not [Michie et al., 1997]. There is increasing interest in the use of more interactive media. While interactive media have been found to be effective in facilitating informed decision-making for other screening tests [O'Connor et al., 1999], the one trial of their use for prenatal screening did not find an advantage over a well written leaflet [Graham et al., 2000]. As web-based decision aids continue to develop it seems likely that the provision of information tailored to a woman's needs will prove a sensitive and effective way of informing her. Mindful of the "digital divide" it will be important that such facilities are available in health care settings to ensure that health discrepancies are not enhanced further by making high quality information available using media unavailable to poorer women.

IV Service delivery
Given that an informed choice is one that reflects a woman's own values, research is needed to determine the ways of presenting tests that enable choice to reflect a woman's values. For example, more women undergo tests when they are presented as part of a routine visit, not requiring a separate visit [Lorenz et al., 1985; Bekker et al., 1993; Dormandy et al., 2002; Tambor et al., 1994.]. It is unclear which system of offering tests results in choices that most reflect women's values. Other aspects of service delivery that may affect the extent to which choices women make are informed is the amount of time health professionals have to present these choices. Only by using a valid measure of informed choice that assesses both knowledge and women's values [eg Marteau et al., 2002] can we ascertain the extent to which different characteristics of service delivery impede or facilitate the making of an informed choice. Given the very large effect service delivery can have on use of testing [Bekker et al., 1993; Tambor et al., 1994], this research question should assume some urgency.

V Decisions after the diagnosis of a fetal anomaly
In contrast to the great volume of research on women's decisions about prenatal testing, there is a dearth of research on women's decisions following the diagnosis of a fetal anomaly. Consequently, little is known about how best to facilitate women's decision making after the diagnosis of a fetal anomaly. There are many barriers to conducting research on this. The numbers of women affected are small, making large multicentered studies a requirement to ask even the most simple, descriptive questions. The diagnosis of a fetal anomaly is invariably a distressing event for women and for their providers, making it difficult to seek consent to participate in research. Creative ways are needed of overcoming these and other barriers to research aimed at determining how best to facilitate informed choices after the diagnosis of a fetal anomaly. Research approaches that merit attention include the use of simulated patients, to study health professionals' counseling, as well as prospective single case studies, to study long term adjustment to the decisions made.
Both the information women receive as well as the emotional and decisional support provided are important [Biesecker, 2001]. The results from a small study, in which health professionals described the information they had recently given parents following the diagnosis of a sex chromosome anomaly, suggest that some parents are being given inadequate and incorrect information on which to base their decisions about whether to continue with the affected pregnancy [Abramsky et al., 2001]. The absence of other studies in this area make it difficult to estimate the scale of this problem.

As well as giving accurate information, it is important that health professionals provide counseling that facilitates informed choices without being directive. While the great majority of women in a recent study reported not being influenced by health professionals in deciding whether or not to continue with an affected pregnancy [Statham and Solmou, 1998], findings from several observational studies suggest otherwise. Three studies show parents are more likely to terminate pregnancies affected by a sex chromosome anomaly when counseled by an obstetrician than by a geneticist or a specialist pediatrician [Holmes-Siedle et al., 1987; Robinson et al., 1989; Marteau et al., submitted]. Such findings reflect evidence from several other studies suggesting that the counseling provided by geneticists tends to be more positive and less directive than that provided by other health professionals [Geller et al., 1993; Marteau et al., 1994]. It is possible that the influence of health professionals on decisions after the diagnosis of a fetal anomaly varies across conditions, exerting a stronger influence with less familiar and less severe conditions. While these cross-sectional data suggest counseling may be influencing decisions, prospective study designs are needed to confirm this. Such studies need to identify aspects of counseling that facilitate and those that impede informed choices following the diagnosis of a fetal anomaly. While there is a consensus that directive counseling is undesirable, there is less consensus on what constitutes the elements of counseling that are desirable, that is, facilitate informed choices.
Until such time as there is evidence concerning the most effective ways of presenting information and providing decisional and emotional support to facilitate informed choices, it may be useful for guidelines to be generated, using consensus development methods [Black et al., 1999]. Alongside health professionals, it would be important that participants include parents of affected children and parents who opted to terminate an affected pregnancy. It would also be important to include, where possible, adults with the condition, given the differences between their views and those of parents with affected children [Conway et al., 1994; Henneman et al., 2001]. The output of such a process would provide an important framework within which counselors could operate. It should not, however, be construed as a straightjacket or a unitary model for counseling. The strength of all counseling lies in the ability of the counselor to establish a warm, empathic relationship within which the needs of the counselee take center stage.

Concluding Comments
There is now good evidence attesting to the variable and sometimes poor information and support given to women offered and undergoing prenatal tests. Enough is known to set basic quality standards that all centers offering prenatal testing should reach. Research now needs to focus upon evaluating different ways of presenting the same information, and the effectiveness of using different media and methods of delivering services. Outcomes need to expand beyond knowledge to incorporate an assessment of women's values to allow evaluation of the extent to which different ways of presenting information and tests allow informed choices to be realized. Evidence is also needed on size of the psychological benefits of choices that are informed.

There has been little research addressing the extent to which services meet the needs of the few women in whom a fetal anomaly is diagnosed. Thirty years after the routine introduction of prenatal diagnostic tests we remain unaware of how women are counseled, the information and support they receive, and how this affects the quality and type of decisions they make. There is an urgent need to fill this gap as a first step towards providing the counseling known to facilitate the best outcomes for women facing such difficult decisions.

Laboratories are required to adhere to quality standards in the conduct of their tests. No such required quality standards exist for the provision of information about such tests. If we value women's ability to make informed choices about prenatal tests as highly as we value reliable laboratory tests, evidence-based quality standards need to be developed for the information women are given at all stages of the process of prenatal testing. This should be a long term objective for this area.

Acknowledgement
Theresa Marteau and Elizabeth Dormandy are funded by The Wellcome Trust.

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