Two-dimensional vs. two- plus four-dimensional ultrasound in pregnancy and the effect on maternal emotional status: a randomized study

OBJECTIVE: To assess whether the addition of four-dimensional (4D) ultrasound to a conventional two-dimensional (2D) scan in the second/third trimester of pregnancy facilitates maternal recognition of specific fetal structures and movements and causes an emotional impact, as subjectively perceived by the woman. METHODS: Fifty-two women were randomly assigned to 2D ultrasound only (Group 1), while 48 women underwent 2D plus 4D ultrasound (Group 2). All the women completed two questionnaires. One questionnaire listed the fetal structures and movements that the women had recognized during the 2D scan or, for those women who also underwent a 4D scan, during the combination of the two; the other questionnaire required the women to score on an analog scale whether they had seen all the fetal parts and movements that they wished to see, whether they were satisfied with the scan, and if the scan had changed for the better their perception of the fetus. A subgroup of 46 women completed the Maternal Antenatal Attachment Scale (MAAS) designed to measure antenatal emotional attachment. RESULTS: Similar percentages of women in the two groups visualized fetal structures and movements, but facial expressions and hand-to-mouth movements were twice as likely to be seen with 4D ultrasound, although this difference did not reach statistical significance. The percentage of women who reported that they had seen all the fetal parts and movements that they wished to see, and of those who were satisfied overall with the scan, were similar in the two groups. There was no difference in the percentage of women who felt that the scan had changed for the better their perception of the fetus. Although the MAAS scores were similar in the two groups, there were more women with positive quality, intensity and global attachment among those who had undergone a 4D scan. Women who had seen all the fetal parts and movements they wished to see (whether with 2D or 2D plus 4D) answered more frequently that the scan had changed for the better their perception of the fetus. CONCLUSION: This randomized study indicates that the addition of 4D ultrasound does not change significantly the perception that women have of their baby nor their antenatal emotional attachment compared with conventional 2D ultrasound.