Investigating the pathways from preconception care to preventing maternal, perinatal and child mortality: A scoping review and causal loop diagram

•A Causal Loop Diagram (CLD) was informed by evidence from 34 meta-analyses.•The CLD uncovers preconception pathways for improving maternal and child health.•It is key to prevent early/repeated pregnancies and optimise nutritional status.•The CLD provides a tool for advocating better integration of preconception care.•Future research should focus on sub-systems and diversify the data sources. In recent years, there has been a growing recognition that developing preconception care provides an opportunity to significantly reduce maternal and child mortality and morbidity. This involves targeting multiple risk factors through a large array of medical, behavioural and social interventions. In this study, we created a Causal Loop Diagram (CLD) to describe several pathways by which a set of preconception interventions may lead to women's improved health and better pregnancy outcomes. The CLD was informed by a scoping review of meta-analyses. It summarises evidence on the outcomes and interventions related to eight preconception risk factors. The authors reviewed literature from two databases (PubMed and Embase) and used the framework developed by Arksey and O'Malley. The CLD includes 29 constructs categorised into five different levels (mortality, causes of death, preconception risk factors, intermediate factors, interventions or policies). The model indicates interconnections between five sub-systems and highlights the role of preventing early and rapidly repeated pregnancies, as well as optimising women's nutritional status in the preconception period. It also shows the prevention of preterm birth as a privileged route for lowering child mortality and morbidity. The CLD demonstrates the potential benefits of strategies that address multiple preconception risk factors simultaneously and can be used as a tool to promote the integration of preconception care into efforts to prevent maternal and child mortality. With further improvements, this model could serve as a basis for future research on the costs and benefits of preconception care.