Evidence-based preconceptional lifestyle interventions.

Although the evidence for the associations between preconceptional risk factors and adverse pregnancy outcomes is extensive, the effectiveness of preconceptional interventions to reduce risk factors and to improve pregnancy outcomes remains partly unclear. The objective of this review is to summarize the available effectiveness of lifestyle interventions prior to pregnancy for women in terms of behavior change and pregnancy outcome. A predefined search strategy was applied in electronic databases, and citation tracking was performed. Study selection was performed by 2 independent reviewers according to predefined criteria for eligibility: The intervention was performed preconceptionally on women regarding alcohol use, smoking, weight, diet/nutrition, physical activity, and folic acid status (fortification and supplementation) to achieve behavior change and/or improve pregnancy outcome. Quality and strength of evidence were assessed by 2 independent reviewers. A total of 4,604 potentially relevant records were identified, of which 44 records met the inclusion criteria. Overall, there is a relatively short list of core interventions for which there is substantial evidence of effectiveness when applied in the preconception period.