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.