High feedback versus low feedback of prenatal ultrasound for reducing maternal anxiety and improving maternal health behaviour in pregnancy

  • Review
  • Intervention

Authors


Abstract

Background

Prenatal ultrasound is one of many techniques used in screening and diagnosis. It gives parents instant access to the images of the fetus. Receiving information promotes knowledge and understanding, but it may also increase maternal anxiety.

Objectives

To compare high feedback versus low feedback during prenatal ultrasound for reducing maternal anxiety and improving maternal health behaviour.

Search methods

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (March 2010), the Central Register of Controlled Trials (The Cochrane Library 2010, Issue 1), MEDLINE (January 1966 to 1 March 2010), and the metaRegister of Controlled Trials (mRCT) (March 2010). We handsearched citation lists of relevant publications. We did not apply any language restrictions.

Selection criteria

Randomized controlled trials (RCTs) of high feedback (women can see the monitor screen and receive detailed visual and verbal explanations) versus low feedback (women can not see the monitor screen and women are given only a summary statement of the scan) during prenatal ultrasound. The primary outcome measure was maternal state anxiety.

Data collection and analysis

Two authors independently assessed trial quality and extracted data. We have expressed results as risk ratio (RR) or mean differences, together with their 95% confidence intervals (CI).

Main results

We included four studies (365 women). Three RCTs(346 participants) reported the effect of high versus low feedback during ultrasound on state anxiety scores (mean difference 0.92, 95% CI -0.58 to 2.43). Two trials (148 participants) reported women's views of the level of feedback. They do not show that women in the high feedback groups are more likely to choose very positive adjectives to describe their feelings after the scan (RR 3.30; 95% CI 0.73 to 14.85). Women who had a high feedback during ultrasound were more likely to stop smoking during pregnancy (one trial, 129 participants; RR 2.93; 95% CI 1.25 to 6.86) and to avoid alcohol during pregnancy (one trial, 129 participants; RR 2.96; 95% CI 1.15 to 7.60).

Authors' conclusions

There is insufficient evidence to support either high or low feedback during a prenatal ultrasound to reduce maternal anxiety and promote health behaviour.

Résumé scientifique

Comparaison de l'échographie prénatale avec informations complètes ou partielles pour réduire l'anxiété maternelle et améliorer les comportements de santé de la mère pendant la grossesse

Contexte

L'échographie prénatale est l'une des nombreuses techniques utilisées pour le dépistage et le diagnostic. Elle permet aux parents de visualiser des images du fœtus. Le retour d'information permet d'améliorer les connaissances et la compréhension, mais peut également accentuer l'anxiété de la future mère.

Objectifs

Comparer l'échographie prénatale avec informations complètes ou partielles pour réduire l'anxiété maternelle et améliorer les comportements de santé de la mère pendant la grossesse.

Stratégie de recherche documentaire

Nous avons effectué une recherche dans le registre des essais cliniques du groupe Cochrane sur la grossesse et la naissance (mars 2010), ainsi que dans le registre Cochrane des essais contrôlés (CENTRAL) (The Cochrane Library 2010, numéro 1), MEDLINE (de janvier 1966 au 1er mars 2010) et le méta-registre des essais contrôlés (mREC) (mars 2010). Nous avons effectué une recherche manuelle dans les bibliographies des publications pertinentes. Nous n'avons appliqué aucune restriction linguistique.

Critères de sélection

Des essais contrôlés randomisés (RCT) sur la comparaison entre une échographie prénatale avec informations complètes (la future mère peut voir l'écran du moniteur et avoir des explications visuelles et verbales détaillées) et partielles (la future mère ne voit pas l'écran et obtient seulement un résumé de l'échographie). Le critère de jugement principal était l'état d'anxiété de la future mère.

Recueil et analyse des données

Deux auteurs ont indépendamment évalué la qualité méthodologique des essais et extrait des données. Les résultats ont été exprimés sous la forme de risques relatifs (RR) avec des intervalles de confiance (IC) à 95 %, ou de différences moyennes (DM).

Résultats principaux

Nous avons inclus quatre études (365 femmes). Trois ECR (346 participants) ont rapporté l'effet comparé d'informations complètes et partielles pendant l'échographie sur les scores d'anxiété (différence moyenne 0,92, IC à 95 % -0,58 à 2,43). Deux essais (148 participants) ont rapporté l'avis des mères sur le niveau du retour d'information. Ces essais n'indiquent pas que les femmes ayant reçu les informations complètes étaient plus susceptibles de choisir des adjectifs très positifs pour décrire leurs sentiments après l'échographie (RR 3,30 ; IC à 95 % 0,73 à 14,85). Les femmes ayant reçu les informations complètes pendant l'échographie avaient plus de chance d'arrêter de fumer (un essai, 129 participants ; RR 2,93 ; IC à 95 % 1,25 à 6,86) et d'éviter de consommer de l'alcool pendant leur grossesse (un essai, 129 participants ; RR 2,96 ; IC à 95 % 1,15 à 7,60).

Conclusions des auteurs

Les preuves sont insuffisantes pour justifier le retour d'information complet ou limité pendant une échographie prénatale pour réduire l'anxiété de la mère et améliorer les comportements de santé.

アブストラクト

妊娠中の母親の不安を軽減し、母親の健康行動を改善するための出生前超音波検査の高フィードバックと低フィードバックの比較

背景

出生前超音波検査は、スクリーニングと診断に用いられる多くの手法のひとつである。超音波検査では、親は胎児の画像を即座にみることができる。情報を受け取ることは、知識と理解を高めるが、母親の不安を増大させることもある。

目的

母親の不安を軽減し、母親の健康行動を改善するための出生前超音波検査中の高フィードバックと低フィードバックを比較する。

検索戦略

Cochrane Pregnancy and Childbirth Group's Trials Register(2010年3月)、Central Register of Controlled Trials(コクラン・ライブラリ 2010年第1号)、MEDLINE(1966年から2010年3月1日まで)、および、metaRegister of Controlled Trials(mRCT)(2010年3月まで)を検索した。関連性のある出版の引用リストをハンドサーチした。言語制限を適用しなかった。

選択基準

出生前超音波検査中の高フィードバック(女性はモニター画面を見ることができ、視覚と言語での詳細な説明を受ける)と低フィードバック(女性はモニター画面を見ることはできず、スキャンの要約説明だけが与えられる)を比較したランダム化比較試験(RCT)。主要アウトカム指標は母親の状態不安であった。

データ収集と分析

2人のレビューアが独自に試験の質を評価し、データを抽出した。結果をリスク比(RR)または平均差およびその95%信頼区間(CI)として表した。

主な結果

4件の研究(女性365例)を採択した。3件のRCT(346例)は、状態不安スコアに対する高フィードバックの効果を低フィードバックと比較し報告した(平均差0.92、95%CI -0.58~2.43)。2件の試験(148例)は、フィードバックのレベルについての女性の見解を報告した。高フィードバック群の女性のほうが、スキャン後に感じたことを記述するのに非常にポジティブな形容詞を選択する可能性が高いことをこれらの試験は示さなかった(RR 3.30;95%CI 0.73~14.85)。超音波検査中に高フィードバックを受けた女性のほうが、妊娠中に禁煙する可能性が高く(1件の試験、129例;RR 2.93;95%CI 1.25~6.86)、妊娠中飲酒を避ける可能性が高かった(1件の研究、129例;RR 2.96;95%CI 1.15~7.60)。

著者の結論

母親の不安を軽減し、健康行動を促すための出生前超音波検査中の高フィードバックと低フィードバックのいずれか一方を支持するにはエビデンスは不十分であった。

訳注

監  訳: 江藤 宏美,2010.11.18

実施組織: 厚生労働省委託事業によりMindsが実施した。

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Plain language summary

Effect of high feedback versus low feedback of prenatal ultrasound on maternal anxiety and health behaviour in pregnancy

Ultrasound is a routine part of prenatal care offered to pregnant women in most countries with developed health services. It is used during prenatal care to help achieve a healthy mother and child. Pregnant women want reassurance and to check that all is normal by verifying fetal life and growth and to exclude fetal abnormalities. The parents are given immediate access to the images of the fetus, which may promote maternal attachment and positive attitudes toward health during the pregnancy. The obstetricians can identify high-risk conditions including multiple pregnancy, abnormalities of amniotic fluid volume and the placenta, fetal anomalies and growth restriction. During high feedback ultrasound scans, women can see the screen and they receive detailed explanations of the images. In low feedback ultrasound scans, only the operator can see the screen and the women are told the results at the end of the scan. High feedback might reduce pregnancy anxiety but it can impact both ways, not only adding excessive stress on the pregnant women and their partners but also on the physicians, especially when there is the possibility of an abnormal finding. We carried out this systematic review to compare high feedback versus low feedback during prenatal ultrasound for reducing maternal anxiety and improving maternal health behaviour and other pregnancy outcomes.

High or low feedback of prenatal ultrasound to reduce women's state of anxiety is not supported by evidence from randomized controlled trials. We included four studies involving 346 pregnant women in the review which looked at this outcome. Two trials with a total of 148 women reported on the women's views on the level of feedback. The women in the high feedback groups were not clearly more likely to choose very positive adjectives to describe their feelings after the scan. One trial with 129 participants reported that women who had high feedback during ultrasound were more likely to stop smoking and avoid alcohol during pregnancy. The trials were reported on between 1985 and 1996.

Résumé simplifié

Comparaison de l'effet de l'échographie prénatale avec informations compètes ou partielles sur l'anxiété maternelle et les comportements de santé pendant la grossesse

L'échographie fait partie des examens prénataux de routine proposés aux femmes enceintes dans la plupart des pays dotés de services de santé développés. Elle est incluse dans les soins prénataux pour améliorer les résultats de santé de la mère et de l'enfant. Les femmes enceintes ont besoin d'être rassurées et d'avoir l'assurance que tout est normal en vérifiant que le fœtus est en vie, que sa croissance est normale et en excluant toute anomalie fœtale. Les parents visualisent immédiatement les images du fœtus, ce qui favorise l'attachement maternel et un comportement de santé positif pendant la grossesse. Les obstétriciens peuvent identifier les situations à haut risque, notamment les grossesses multiples, les anomalies du volume du liquide amniotique et du placenta, les anomalies du fœtus et les retards de croissance. Pendant une échographie avec informations complètes, la femme peut voir l'écran et avoir des explications détaillées des images. Pendant une échographie avec informations partielles, seul l'opérateur voit l'écran ; la femme obtient les résultats à la fin de l'échographie. L'échographie avec informations complètes peut réduire l'anxiété de la femme enceinte, mais peut également avoir l'effet inverse ; elle peut, en effet, renforcer le stress de la future mère et de son partenaire, mais également celui du médecin, en particulier en cas de détection d'une anomalie. Nous avons réalisé cette revue systématique pour comparer une échographie prénatale avec informations complètes ou partielles pour réduire l'anxiété maternelle et améliorer les comportements de santé de la mère et les autres résultats de santé de la grossesse.

Les essais contrôlés randomisés ne fournissent aucune preuve d'un effet de l'échographie prénatale avec informations complètes ou partielles sur l'état d'anxiété de la future mère. Nous avons inclus dans cette revue quatre études portant sur 346 femmes enceintes étudiant ce critère de jugement. Deux essais portant sur 148 femmes donnent le point de vue de ces dernières sur le niveau du retour d'information. Les femmes bénéficiant des informations complètes n'étaient pas clairement plus susceptibles de choisir des adjectifs très positifs pour décrire leurs sentiments après l'échographie. Un essai sur 129 femmes rapporte que les femmes ayant bénéficié d'informations complètes pendant l'échographie avaient plus de chance d'arrêter de fumer et de consommer de l'alcool pendant leur grossesse. Les études ont été rapportées entre 1985 et 1996.

Notes de traduction

Traduit par: French Cochrane Centre 12th November, 2012
Traduction financée par: Ministère du Travail, de l'Emploi et de la Santé Français

Background

Routine prenatal care and ultrasonography

Ultrasound may be used as a tool to diagnose complications that may arise during pregnancy (including multiple pregnancy, fetal growth restriction, placenta praevia). It may also be offered as part of routine obstetric care in many countries with developed healthcare services (Bricker 2000; Garcia 2002; Jahn 2002; Lalor 2006; Sen 2003).

Routine prenatal ultrasonography has become an integral part of the psychological experience of having a baby (Harris 2004). Women may seek prenatal ultrasonography for reassurance and to make informed decisions later in pregnancy. Other reasons why pregnant women request a prenatal ultrasound in the absence of clinical indications include their desire to know the sex of the fetus, to exclude fetal anomalies, to verify fetal life and to assess fetal growth. Those reasons vary according to the parity; duration of gestation; prior obstetric history (e.g. prior miscarriage or fetal loss); and personal factors. Lower income was more significantly related to wanting to see the baby and wanting an ultrasound picture, whereas higher income was more significantly related to checking that all was normal and for reassurance. Women in their first pregnancy were more likely to want themselves and the father to see the baby. Women who had given birth previously were more likely to want reassurance, as were women with a previous miscarriage or induced abortion. Women who would agree to an abortion in case of fetal trisomies were more likely to want to know about abnormalities. Women in the second trimester were more likely to want to check for abnormalities and appropriate fetal growth than those in the first trimester (Gudex 2006).

Description of the intervention

The prenatal real time ultrasound is one of a range of techniques used in screening and diagnosis, but it differs from most others because it gives parents instant access to the images of the fetus (Garcia 2002). In addition to instant access to a fetal image, the care giver provides information (feedback) to the pregnant woman. In current practice there are two types of feedback depending on the amount of information given to the pregnant woman. During high feedback ultrasound scans, women can see the screen and receive detailed explanations, while in low feedback ultrasound scans, only the operator can see the screen and the women are told the results at the end of the scan (Bricker 2000; Field 1985; Reading 1982; Reading 1985; Zlotogorski 1996). Feedback includes how the physicians provide information about the examination procedure itself, as well as how they inform the pregnant woman about her pregnancy and whether or not a complication is detected (Gotzmann 2001).

How the intervention might work

The amount of information given to the pregnant woman may have an impact on the level of state anxiety of a pregnant woman, maternal-fetal attachment and health attitudes during pregnancy e.g. cessation of smoking and alcohol consumption (Crandon 1979; Janus 1980; Lobel 2008; Sjöström 2002; Teixeira 1999). The impact of the amount of feedback might be influenced by clinical, for example duration of gestation and parity, and demographic factors that might independently influence anxiety and health attitudes in pregnant women.

State anxiety is a transitory emotional state and refers to a palpable reaction or process taking place at a given time and level of intensity. State anxiety, unlike trait anxiety, is affected by situational circumstances e.g. undergoing a diagnostic test as an ultrasound scan. It must be noted that the individual differences in reactions (called trait anxiety) (Endler 2001) may have a more profound impact on state anxiety than the timing or nature of the feedback itself (Zlotogorski 1995).

The tools used to assess anxiety include Spielberger State-Trait Anxiety Inventory (STAI) (Spielberger 1983) and Beck Anxiety Investory (Beck 1988). The STAI differentiates between temporary or emotional state anxiety versus longstanding personality trait anxiety in adults. The STAI contains four-point Likert items. The instrument is divided into two sections, each having 20 questions. The first sub scale measures state anxiety, the second measures trait anxiety. The range of scores is 20-80, the higher score indicating greater anxiety. Approximately 10 minutes are required for adults to complete the STAI.

High feedback during a prenatal ultrasound might reduce pregnancy anxiety, particularly for the primigravida women (Field 1985). High feedback might also increase maternal-fetal attachment and promote positive attitudes toward health during pregnancy (Boukydis 2006; Reading 1982). But it can impact both ways, not only adding excessive stress on the pregnant women and their partners, but also on the physicians, especially when there are fetal anomalies (Gotzmann 2001). Needless to say the amount of information given to the pregnant woman in case of detecting an ultrasonographic soft marker is very important in light of the relatively high false-positive rates of ultrasonographic soft markers. In a recent study including 215 women, it was found that women with a possible soft ultrasound findings who were referred for further tests had significantly higher state anxiety than women who were referred because of their advanced age (Hoskovec 2008). Therefore, it seems very important to know what to say and how to say it and It should be acknowledged that a number of factors contribute to successful detection of anomalies, including the type of anomaly, gestational age at scanning, the skill of the sonographer and the ultrasound machine used (Bricker 2000).

Whereas, low feedback with a less detailed approach may be preferable for a routine screening program for low-risk pregnancy, as extensive provision of information about possible abnormal finding can cause unnecessary anxiety until further scans or tests resolve the issue (Lalor 2006). The clinical situation of 'absence of reassuring findings' during a scan might make some obstetricians provide a low level of feedback to avoid unnecessary anxiety. A recent study has shown that, contrary to their expectation of reassurance, most antenatal care attendees are warned about possible abnormalities, which often lead to further investigations and cause considerable anxiety. Two-thirds (67.2%) of antenatal care attendees reported suspicious or abnormal findings, almost half of which (45.1%) resulted from routine ultrasound scans. More than half (53.2%) of those with suspicious findings had higher state anxiety scores. The suspected problem often did not materialize: 13 of 16 suspected malformations and 34 of 42 suspected growth-retarded babies were in the normal range (Petersen 2008).

Obstetricians should be careful not to give a false reassurance while providing a detailed high feedback. This false reassurance may be due to women's lack of knowledge about what ultrasound can and cannot test for. One more issue is whether informing the parents of the fetal sex is part of the “high feedback”. The effect this information has on the parents may colour the rest of the results. The effect would also be influenced by whether the sex is the desired sex for this baby.

Why it is important to do this review

A systematic review is needed to identify whether to provide high feedback or low feedback during prenatal ultrasound examinations; and whether high or low feedback improves maternal positive health attitudes during pregnancy and reduces maternal state anxiety.

Objectives

To compare high feedback versus low feedback during prenatal ultrasound for reducing maternal anxiety and improving maternal health behavior and pregnancy outcomes.

Methods

Criteria for considering studies for this review

Types of studies

Randomized controlled trials (RCTs). We did not include quasi-randomized trials.

Types of participants

Pregnant women undergoing routine ultrasound during pregnancy.

Types of interventions

High feedback versus low feedback during ultrasound during routine antenatal care.

Types of outcome measures

Primary outcomes
  1. Maternal anxiety measured by State Trait Anxiety Inventory as defined by the investigators of each included study.

Secondary outcomes
  1. Cessation of alcohol

  2. Cessation of smoking

  3. Women's views of level of feedback

Search methods for identification of studies

Electronic searches

We contacted the Trials Search Co-ordinator to search the Cochrane Pregnancy and Childbirth Group’s Trials Register (March 2010). 

The Cochrane Pregnancy and Childbirth Group’s Trials Register is maintained by the Trials Search Co-ordinator and contains trials identified from:

  1. quarterly searches of the Cochrane Central Register of Controlled Trials (CENTRAL);

  2. weekly searches of MEDLINE;

  3. handsearches of 30 journals and the proceedings of major conferences;

  4. weekly current awareness alerts for a further 44 journals plus monthly BioMed Central email alerts.

Details of the search strategies for CENTRAL and MEDLINE, the list of handsearched journals and conference proceedings, and the list of journals reviewed via the current awareness service can be found in the ‘Specialized Register’ section within the editorial information about the Cochrane Pregnancy and Childbirth Group.

Trials identified through the searching activities described above are each assigned to a review topic (or topics). The Trials Search Co-ordinator searches the register for each review using the topic list rather than keywords. 

In addition, we searched CENTRAL (The Cochrane Library 2010 Issue 1), MEDLINE (January 1966 to 1 March 2010) and the metaRegister of Controlled Trials (mRCT) (March 2010) using the search strategies detailed in Appendix 1

Searching other resources

We handsearched citation lists of relevant publications.

We did not apply any language restrictions.

Data collection and analysis

The methodology for data collection and analysis followed the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2008).

Selection of studies

Both review authors assessed all potential studies identified as a result of the search strategy. We resolved any disagreement through discussion.

Data extraction and management

We designed a form to extract data. Both review authors extracted the data using the agreed form. If the study was presented only as abstract, we tried to contact the researchers. We summarized the details of the intervention in the review. We resolved discrepancies through discussion. We used the Review Manager software (RevMan 2008) to double enter all the data or a sub sample.

Assessment of risk of bias in included studies

Two review authors (A Nabhan and M Faris) independently assessed risk of bias for each study using the criteria outlined in the Cochrane Handbook for Systematic Reviews of Interventions (Higgins 2008). There were no disagreements on the assessment of risk of bias in the included study.

(1) Sequence generation (selection bias)

We described for each included study the methods used to generate the allocation sequence in sufficient detail to allow an assessment of whether it should produce comparable groups. We assessed the methods as:

  • adequate (any truly random process, e.g. random number table; computer random number generator);

  • inadequate (any non-random process, e.g. odd or even date of birth; hospital or clinic record number); or

  • unclear.

(2) Allocation concealment (selection bias)

We described for each included study the method used to conceal the allocation sequence in sufficient detail and determined whether intervention allocation could have been foreseen in advance of, or during recruitment, or changed after assignment. We assessed the methods as:

  • adequate (e.g. telephone or central randomisation; consecutively numbered sealed opaque envelopes);

  • inadequate (open random allocation; unsealed or non-opaque envelopes);

  • unclear.

(3) Blinding (performance bias)

We described for each included study all the methods used, if any, to blind study participants and personnel from knowledge of which intervention a participant received. We also provided information on whether the intended blinding was effective. Where blinding was not possible, we assessed whether the lack of blinding was likely to have introduced bias. We assessed blinding separately for different outcomes or classes of outcomes. With an intervention such as allocation to high feedback rather than low feedback during ultrasound scan, it is not practically feasible to blind women and clinical staff to treatment allocation, but it may be possible to blind outcome assessors

We assessed the methods as:

  • adequate, inadequate or unclear for outcome assessors.

(4) Incomplete outcome data (attrition bias)

We described for each included study, and for each outcome or class of outcomes, the completeness of data including attrition and exclusions from the analysis. We stated whether attrition and exclusions were reported, the numbers included in the analysis at each stage (compared with the total randomized participants), reasons for attrition or exclusion where reported, and whether missing data were balanced across groups or were related to outcomes. Where sufficient information was reported, or could be supplied by the trial authors, we re-included missing data in the analyses which we undertook. We assessed methods as:

  • adequate;

  • inadequate (missing data greater than 20% of the sample);

  • unclear.

(5) Selective reporting bias

We described for each included study how we examined the possibility of selective outcome reporting bias and what we found.

We assessed the methods as:

  • adequate (where it is clear that all of the study's pre-specified outcomes and all expected outcomes of interest to the review have been reported);

  • inadequate (where not all the study's pre-specified outcomes have been reported; one or more reported primary outcomes were not pre-specified; outcomes of interest are reported incompletely and so cannot be used; study fails to include results of a key outcome that would have been expected to have been reported);

  • unclear.

(6) Other sources of bias

We described for each included study any important concerns we have about other possible sources of bias.

We assessed whether each study was free of other problems that could put it at risk of bias:

  • yes;

  • no;

  • unclear.

(7) Overall risk of bias

We made explicit judgements about whether studies were at high risk of bias, according to the criteria given in the Handbook (Higgins 2008). With reference to (1) to (6) above, we assessed the likely magnitude and direction of the bias and whether we considered it is likely to impact on the findings. We explored the impact of the level of bias through undertaking sensitivity analyses.

Measures of treatment effect

We carried out statistical analysis using the Review Manager software (RevMan 2008).

Dichotomous data

For dichotomous data, we presented results as summary risk ratio with 95% confidence intervals.

Continuous data

For continuous data, we used the mean difference if outcomes are measured in the same way between trials. We used the standardized mean difference to combine trials that measure the same outcome, but use different methods.

Unit of analysis issues

Cluster-randomized trials

We did not include any cluster-randomized trials in the analyses in addition to individually randomized trials.

Dealing with missing data

We analyzed data on all participants with available data in the group to which they were allocated, regardless of whether or not they received the allocated intervention.

Assessment of heterogeneity

We applied tests of heterogeneity between trials, if appropriate, using the I2 statistic. If we identified high levels of heterogeneity among the trials (exceeding 50%), we explored it by prespecified subgroup analysis and perform sensitivity analysis. We used a random-effects meta-analysis as an overall summary if we considered this appropriate.

Assessment of reporting biases

Where we suspected reporting bias (see 'Selective reporting bias' above), we planned to contact study authors asking them to provide missing outcome data.

Data synthesis

We used fixed-effect meta-analysis for combining data in the absence of significant heterogeneity if trials were sufficiently similar. If we found heterogeneity, we explored this by sensitivity analysis followed by random-effects if required.

Subgroup analysis and investigation of heterogeneity

We conducted planned subgroup analyses classifying whole trials by interaction tests as described by Deeks 2001.

We carried out subgroup analysis by timing of intervention, as it is plausible that the level of feedback might be of greater impact on maternal anxiety and her health attitude if provided early in pregnancy.

Sensitivity analysis

We carried out sensitivity analysis to explore the effect of trial quality assessed by concealment of allocation, by excluding studies with clearly inadequate allocation of concealment.

Results

Description of studies

See: Characteristics of included studies; Characteristics of excluded studies.

We have provided descriptions of studies in the 'Characteristics of included studies' and 'Characteristics of excluded studies' tables.

Results of the search

We identified seven potentially eligible studies (Boukydis 2006; Cox 1987; Field 1985; Reading 1985; Reading 1982; Salkovskis 2001; Zlotogorski 1996). (We identified one additional trial report in an updated search after the analysis had been carried out (Stotts 2009). This will be assessed when the review is updated.)

Included studies

We included four studies (365 participants) (Field 1985; Reading 1985; Reading 1982; Zlotogorski 1996). All included studies compared low feedback and high feedback during ultrasound scan in pregnancy.

Excluded studies

We excluded three studies: Boukydis 2006 and Salkovskis 2001 did not compare high feed back and low feedback during ultrasound scan. Cox 1987 was a quasi-randomized trial.

Risk of bias in included studies

We have provided detailed descriptions of the risk of bias in the included studies in the risk of bias tables.

Allocation

In the four included studies (Field 1985; Reading 1985; Reading 1982; Zlotogorski 1996), there was neither a description of the method of sequence generation nor the method used for allocation concealment.

Blinding

None of the four included trials included any description of blinding for any of the outcomes and whether the outcome assessors were blind to the group allocation.

Incomplete outcome data

In the Zlotogorski 1996 study, 211 women were the subjects recruited (three subjects with findings of congenital fetal malformations or other pathological findings were excluded, 10 subjects dropped out at different stages of the study and 15 subjects failed to complete the questionnaires). One participant was never accounted for in the trial. Therefore, only 182 women were available for analysis. For the state anxiety scores, data from 177 participants were recorded. The trial did not account for the missing five participants.

Selective reporting

There is no evidence that there was selective reporting of outcomes.

Other potential sources of bias

There is no evidence that there were other potential sources of bias.

Effects of interventions

Maternal anxiety

All included trials used the same tool, the State Trait Anxiety Inventory which is a valid tool for use in pregnant adults to assess the effect of intervention on maternal anxiety. Three trials including 346 women (Field 1985; Reading 1982; Zlotogorski 1996) provided data that allowed quantitative analysis with a mean difference 0.92, 95% CI -0.58 to 2.43 (Analysis 1.1). We carried out the subgroup analysis: high feedback versus low feedback in second trimester pregnancy ultrasound. Only one trial (Field 1985), including 40 women, reported data on the effect of level of feedback during second trimester routine ultrasound scan on maternal anxiety and showed no difference between high and low feedback (mean difference 2.00, 95% CI -3.40 to 7.40).

Secondary outcomes

Health behaviour

Alcohol consumption

One trial (Reading 1982; 129 participants) reported the effect of the level of feedback on alcohol consumption during pregnancy. Women who had a high feedback during ultrasound were more likely to avoid alcohol during pregnancy (RR 2.96; 95% CI 1.15 to 7.60) see Analysis 1.2.

Smoking

One trial (Reading 1982; 129 participants) reported the effect of the level of feedback on smoking during pregnancy. Women who had a high feedback during ultrasound were more likely to stop smoking during pregnancy (RR 2.93; 95% confidence interval (CI) 1.25 to 6.86), see Analysis 1.3.

Women's views of level of feedback

Two trials (Reading 1982; Reading 1985; 148 participants) reported women's views of the level of feedback. Women in the high feedback groups were not more likely to choose very positive adjectives to describe their feelings after the scan (RR (random effects) 3.30; 95% CI 0.73 to 14.85; see Analysis 1.4). It has to be noted that there was substantial heterogeneity among studies (I² = 88%) that could not be explained and therefore we used a random-effects meta-analysis.

Discussion

We conducted this systematic review to compare high feedback versus low feedback during prenatal ultrasound for reducing maternal state anxiety and improving maternal health behaviour. Receiving information promotes knowledge and understanding, but it may also increase state anxiety (Yee 2007).

Summary of main results

Four RCTs (365 women) reported the impact of level of feedback during ultrasound examination on maternal (pregnancy) state anxiety and prenatal health attitudes. There is insufficient evidence regarding what amount of feedback works better to reduce state anxiety. There was no difference between high and low feedback regarding women's views of the level of feedback. Only one small trial reported the impact of feedback level on the health attitudes of women, namely smoking cessation and alcohol consumption. Women who had high level feedback during ultrasound were more likely to stop smoking and avoid alcohol during pregnancy.

Overall completeness and applicability of evidence

The four included trials are not sufficient to address an important issue in our daily practice. Currently, there are no practice guidelines or consensus on the amount of information given to pregnant women and their families and who should do that, particularly in low-risk pregnancy.

Quality of the evidence

The results from this systematic review do not allow a robust conclusion regarding the impact of the level of feedback on maternal state anxiety. In all the included RCTs, it is unclear how randomization (both sequence generation and allocation concealment) was implemented. The sample size in all four included trials was not sufficient to address the outcomes sought. This very small number of participants in all included studies is a limitation to information.

Potential biases in the review process

We identified all relevant studies pertinent to the review question. However, not all outcomes of interest were reported in all included trials.

Agreements and disagreements with other studies or reviews

One prior report has systematically reviewed trials regarding the level of feedback during an ultrasound scan as part of a large work on women’s views of pregnancy ultrasound (Bricker 2000; Garcia 2002). This earlier review claimed that women in the high feedback groups are more likely to choose very positive adjectives to describe their feelings after the scan. We could not find evidence from the included RCTs to show an impact of the amount of information provided on maternal state anxiety and women's views of the scan.

On the other hand, we have shown that women in the high feedback group were more likely to act positively towards cessation of smoking and alcohol consumption during pregnancy. Others have not found that high feedback has an influence on smoking and other aspects of health behaviour (Bricker 2000; Garcia 2002).

Authors' conclusions

Implications for practice

There is insufficient evidence to support either high or low feedback during an ultrasound scan in pregnancy to have a favourable influence on maternal anxiety or health behaviour during pregnancy.

Implications for research

The question of the amount of information delivered to women and their families needs to be properly addressed in large, well designed and conducted RCTs. It might not be possible to conduct such studies in the majority of developed countries where there is the expectation that women are provided with high feedback during their ultrasound examinations.

Further trials are required:

  • to examine clinical and demographic factors that might independently influence anxiety in a low-risk population;

  • to examine the effect of level of feedback on positive health attitude during pregnancy.

Acknowledgements

MS Ahmed-Tawfik, who assisted AF Nabhan in developing the first draft of the protocol.

As part of the pre-publication editorial process, this review has been commented on by three peers (an editor and two referees who are external to the editorial team), a member of the Pregnancy and Childbirth Group's international panel of consumers and the Group's Statistical Adviser.

Data and analyses

Download statistical data

Comparison 1. High feedback versus low feedback of routine prenatal ultrasound
Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size
1 Maternal anxiety3 Mean Difference (IV, Fixed, 95% CI)Subtotals only
1.1 Throughout pregnancy3346Mean Difference (IV, Fixed, 95% CI)0.92 [-0.58, 2.43]
1.2 In the second trimester140Mean Difference (IV, Fixed, 95% CI)2.0 [-3.40, 7.40]
2 Cessation of alcohol1129Risk Ratio (M-H, Fixed, 95% CI)2.96 [1.15, 7.60]
3 Cessation of smoking1129Risk Ratio (M-H, Fixed, 95% CI)2.93 [1.25, 6.86]
4 Women's views of level of feedback2148Risk Ratio (M-H, Random, 95% CI)3.30 [0.73, 14.85]
Analysis 1.1.

Comparison 1 High feedback versus low feedback of routine prenatal ultrasound, Outcome 1 Maternal anxiety.

Analysis 1.2.

Comparison 1 High feedback versus low feedback of routine prenatal ultrasound, Outcome 2 Cessation of alcohol.

Analysis 1.3.

Comparison 1 High feedback versus low feedback of routine prenatal ultrasound, Outcome 3 Cessation of smoking.

Analysis 1.4.

Comparison 1 High feedback versus low feedback of routine prenatal ultrasound, Outcome 4 Women's views of level of feedback.

Appendices

Appendix 1. Search strategies for CENTRAL, MEDLINE and mRCT

CENTRAL

#1 MeSH descriptor Ultrasonography, Prenatal explode all trees
#2 ultraso*
#3 pregnan* or antenatal* or prenatal* or antepart*
#4 (#2 AND #3)
#5 (#1 OR #4)
#6 feedback or anxiety or attitude* or psychol*
#7 MeSH descriptor Maternal Behavior explode all trees
#8 MeSH descriptor Mothers explode all trees with qualifier: PX
#9 (#6 OR #7 OR #8)
#10 (#5 AND #9)

MEDLINE

1 exp Ultrasonography, Prenatal/
2 exp Ultrasonography/
3 (pregnan$ or prenatal$ or antenatal$ or antepart$)
4 2 and 3
5 1 or 4
6 feedback.tw. or exp Feedback/ or exp Feedback, Psychological/
7 exp Mothers/px [Psychology]
8 exp Attitude/
9 6 or 7 or 8
10 9 and 5

mRCT

ultraso% AND pregnan%

History

Protocol first published: Issue 3, 2008
Review first published: Issue 4, 2010

Contributions of authors

AF Nabhan proposed the topic and developed the first draft of the protocol. AF Nabhan edited all the revised drafts of the protocol. Mohamed Faris reviewed and commented on the final draft protocol. Both authors contributed to analysis and interpretation of data; drafting the review and revising it critically for important intellectual content; and final approval of the version to be published.

Declarations of interest

None known.

Sources of support

Internal sources

  • No sources of support supplied

External sources

  • Department of Obstetrics and Gynecology, Ain Shams University, Egypt.

Differences between protocol and review

None.

Characteristics of studies

Characteristics of included studies [ordered by study ID]

Field 1985

MethodsWomen were randomly assigned to either a feedback or no feedback group.
Participants40 pregnant women who were referred for ultrasound assessment of gestational age. They did not differ in background characteristics including age, education, socioeconomic status or ethnicity. Half of the sample was primiparous.
InterventionsWomen assigned to feedback group could see the monitor and were given a running description of the fetal anatomy, measurements and movements. In the no feedback group, women could not see the monitor and they were given only a summary statement of the scan.
OutcomesMaternal anxiety using the Spielberger STAI, fetal movement, maternal sleep behavior, neonatal behavior, neonatal activity level and birthweight.
NotesUSA.
Risk of bias
ItemAuthors' judgementDescription
Adequate sequence generation?UnclearThe study does not include any description of sequence generation.
Allocation concealment?UnclearThe study does not include any description of allocation concealment.
Blinding?
All outcomes
UnclearThe study does not indicate if outcome assessors were blind to allocation
Incomplete outcome data addressed?
All outcomes
Yes 
Free of selective reporting?Yes 
Free of other bias?Yes 

Reading 1982

MethodsWomen were randomly assigned at their first clinical visit (10-14 weeks) to either a high feedback (number = 67) or low feedback (number = 62) groups. Women were asked to complete the STAI before and after the scan. They were also asked to rate their attitude toward receiving a scan and to describe the emotional state at the time by selecting the most appropriate word from the Subjective Stress Scale.
ParticipantsA consecutive series of primiparous Caucasian women fulfilling the selection criteria of obstetrically "low risk" and attending King's College hospital antenatal booking clinics, were studied. Mothers with a history of previous miscarriages or having undergone extended (more than 2 months) infertility treatment were excluded, along with those identified by accredited criteria as being at risk of congenital malformation.
InterventionsWomen assigned to high feedback group could see the monitor and were given standardized visual and verbal feedback as to fetal size, shape and movement. In the low feedback group, women could not see the monitor and were not given specific visual or verbal feedback. They only received a global evaluation of the form "all is well". The examination was of comparable duration and the operator interacted in a similarly reassuring pattern as with high feedback women.
Outcomes

STAI score

Maternal rating of feelings towards being pregnant and towards the fetus

Attitude toward receiving a scan and the emotional state at the time

Cessation of alcohol

Cessation of smoking

NotesUK
Risk of bias
ItemAuthors' judgementDescription
Adequate sequence generation?UnclearThe study does not include any description of sequence generation.
Allocation concealment?UnclearThe study does not include any description of allocation concealment.
Blinding?
All outcomes
UnclearThe study does not indicate if outcome assessors were blind to allocation.
Incomplete outcome data addressed?
All outcomes
Yes 
Free of selective reporting?Yes 
Free of other bias?Yes 

Reading 1985

MethodsThe women were assigned at random to one of four conditions: (1) high-feedback ultrasonography (number = 11), (2) low-feedback ultrasonography (number = 8), fetal monitoring (number = 11), and video control (number = 7). All women were informed that they would be taking part in a study of attitudes towards ultrasonography. None of the women approached refused to participate, and all signed informed consent forms. Before and after the procedure the women completed the state scale of the STAI. Immediately following the procedure the women were asked to select the word best describing their emotional state then from the Subjective Stress Scale, which consists of a series of adjectives describing such states.
ParticipantsA consecutive series of women attending the USC/LAC Women's hospital prenatal clinic for ultrasonography was studied.
InterventionsWomen assigned to high feedback group (number = 11) could see the monitor during their real time examination and a nurse pointed out the features visualized. In the low feedback group (number = 8), women could not see the monitor and so received only global feedback, in the form of "all appears to be well".
Outcomes

1. STAI scores

2. Emotional state following the procedure

NotesUK
Risk of bias
ItemAuthors' judgementDescription
Adequate sequence generation?UnclearThe study does not include any description of sequence generation.
Allocation concealment?UnclearThe study does not include any description of allocation concealment.
Blinding?
All outcomes
UnclearThe study does not indicate if outcome assessors were blind to allocation.
Incomplete outcome data addressed?
All outcomes
Yes 
Free of selective reporting?Yes 
Free of other bias?Yes 

Zlotogorski 1996

  1. a

    STAI: State Trait Anxiety Inventory

MethodsSubjects were randomly assigned to one of two feedback conditions, high feedback and low feedback during an ultrasound examination. All subjects completed the STAI before and after the ultrasound examination.
ParticipantsThe subjects for the study were 211 pregnant women (4 to 41 weeks' gestation) who underwent an ultrasound examination. Three subjects with findings of congenital fetal malformations or other pathological findings were excluded. In addition, 10 subjects who dropped out at different stages of the study and 15 subjects who failed to complete the questionnaires were also excluded. The final sample of 182 women was reported in the results.
InterventionsWomen assigned to high feedback group were shown the monitor screen and were given a standardized visual and verbal feedback of fetal heart, head and limbs. Finally printed pictures of what was seen on the monitor were handed to the subjects by the staff. In the low feedback group, women were not able to see the monitor and the doctor limited himself to providing standardized verbal feedback: "head ... normal, heart ... normal, limbs ... normal, everything ... normal". Printed pictures were not handed to the subjects.
OutcomesMaternal STAI scores.
NotesIsrael
Risk of bias
ItemAuthors' judgementDescription
Adequate sequence generation?UnclearThe study does not include any description of sequence generation.
Allocation concealment?UnclearThe study does not include any description of allocation concealment.
Blinding?
All outcomes
UnclearThe study does not indicate if outcome assessors were blind to allocation.
Incomplete outcome data addressed?
All outcomes
Unclear211 women were the subjects recruited (3 subjects with findings of congenital fetal malformations or other pathological findings were excluded, 10 subjects dropped out at different stages of the study and 15 subjects failed to complete the questionnaires). One participant was never accounted for in the trial. Therefore, only 182 women were reported in the results. For the state anxiety scores, data from 177 participants were recorded. The trial did not account for the missing 5 participants.
Free of selective reporting?Yes 
Free of other bias?Yes 

Characteristics of excluded studies [ordered by study ID]

StudyReason for exclusion
  1. a

    RCT: randomized controlled trial

Boukydis 2006This RCT did not compare high and low feedback during an ultrasound scan.
Cox 1987Women were consecutively assigned to either a low feedback or a high feedback during ultrasound scan.
Salkovskis 2001This RCT did not compare high and low feedback during a routine ultrasound scan.

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