Informed consent: providing information about prenatal examinations.

Background: Choice in prenatal care has moved on from a paternalistic approach, to increased patient autonomy and informed decision-making. This review summarises the existing literature on the information of pregnant women about prenatal examinations. The extent to which information about Down syndrome and screening tests empowers informed decision-making are investigated, as are different ways of expressing a risk estimate.

Results: Knowledge scores can be improved and decisional conflict reduced by group counselling, individual sessions, and by use of leaflets. None of the interventions leads to a raise in anxiety scores or influence uptake rates. Satisfaction with information provided was found unrelated to level of knowledge, but associated with having expectations for information met. Information on Down syndrome is missing (13-21%), or restricted (13%), limitations of screenings tests rarely mentioned, and written materials often insufficient. Women experience risk expressed as proportions or relative risk ratio significantly higher than percentage, number needed to treat, or absolute risk reduction. More women correctly understand relative risk reduction compared to absolute risk reduction and number needed to treat (60 versus 42 and 30%). Using medical words rather than lay terms significantly alter risk perception.

Conclusions: Information can increase the level of knowledge and reduce decisional conflict, without raising anxiety scores. A clarification of the women's expectations seems paramount to obtain a perception of good information and informed consent. The information provided about Down syndrome and screening tests does not empower an informed consent based on relevant knowledge.