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.
To compare high feedback versus low feedback during prenatal ultrasound for reducing maternal anxiety and improving maternal health behavior and pregnancy outcomes.
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
- Maternal anxiety measured by State Trait Anxiety Inventory as defined by the investigators of each included study.
- Cessation of alcohol
- Cessation of smoking
- Women's views of level of feedback
Search methods for identification of studies
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:
- quarterly searches of the Cochrane Central Register of Controlled Trials (CENTRAL);
- weekly searches of MEDLINE;
- handsearches of 30 journals and the proceedings of major conferences;
- 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
(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);
(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:
- inadequate (missing data greater than 20% of the sample);
(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);
(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:
(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).
For dichotomous data, we presented results as summary risk ratio with 95% confidence intervals.
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
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 I
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.
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.
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.
Description of studies
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.)
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.
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.
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.
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.
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
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).
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.
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.
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).
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:
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
- Top of page
- Authors' conclusions
- Data and analyses
- Contributions of authors
- Declarations of interest
- Sources of support
- Differences between protocol and review
- Index terms
Appendix 1. Search strategies for CENTRAL, MEDLINE and mRCT
#1 MeSH descriptor Ultrasonography, Prenatal explode all trees
#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)
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
ultraso% AND pregnan%
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
Sources of support
- No sources of support supplied
- Department of Obstetrics and Gynecology, Ain Shams University, Egypt.
Differences between protocol and review
Medical Subject Headings (MeSH)
*Feedback, Psychological; *Health Behavior; Alcohol Drinking [prevention & control]; Anxiety [*prevention & control]; Communication; Maternal Behavior [*psychology]; Randomized Controlled Trials as Topic; Smoking [prevention & control]; Ultrasonography, Prenatal [*psychology]
MeSH check words
Female; Humans; Pregnancy
* Indicates the major publication for the study