Caring for the child before conception: The need for preconception cohorts to optimize child health and development

The perinatal period is an important and highly sensitive time for future health and development of children. Our understanding of the early determinants of children's development is mainly based on cohort studies starting during pregnancy. However, it is possible that factors occurring before conception, during the preconception phase, might have an impact on a child's future health and development. Interest in factors occurring during preconception is relatively new, and there are few recommendations and guidelines for developing this field of research. This article has four main goals: 1) to discuss the limitations of current knowledge in this field; 2) to highlight the importance of the preconception period for children's future health and development; 3) to present crucial factors to consider for building optimal preconception cohorts; and 4) to recognize the importance of this period for improving public health recommendations for birthing parents. Given the relatively recent scientific interest in the preconception period, there is a significant need for more well-conducted cohort studies to increase knowledge on healthy child development and factors that can impair or promote it. A growing body of evidence suggests that exposure to preconception risk factors can have lasting adverse effects on the offspring, highlighting the need to expand our knowledge about possible factors influencing child development and occurring prior to conception. The preconception period could be a sensitive window for interventions promoting children's health and development, and more research is needed to determine how to improve these outcomes across the lifespan.