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

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 (12 May 2015), the Central Register of Controlled Trials (The Cochrane Library 2015, Issue 5), MEDLINE (January 1966 to 12 May 2015), and the ISRCTN Registry (12 May 2015). We handsearched citation lists of relevant publications. We did not apply any language or date restrictions.


SELECTION CRITERIA
Randomised 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 review authors independently assessed trials for inclusion and risk of bias, extracted data and checked for accuracy. We have expressed results as risk ratio (RR) or mean differences (MD), 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 (MD) 0.92, 95% confidence interval (CI) -0.58 to 2.43; participants = 346; three studies, low quality evidence). 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 (risk ratio (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 (RR 2.93, 95% CI 1.25 to 6.86; participants = 129; one study; low quality evidence) and to avoid alcohol during pregnancy (RR 2.96, 95% CI 1.15 to 7.60; participants = 129; one study; low quality evidence). Downgrading of evidence was based on the unclear risk of bias of included studies, wide CI crossing the line of no effect or presence of heterogeneity.


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.