Using the Lausanne Trilogue Play to assess development of father-mother-infant interactions from pregnancy till the baby's 9th month.

Background: This study takes its theoretical start from the Lausanne Triadic Paradigm which describes the fathermother- infant primary triangle – which starts developing during pregnancy – as one of the primary matrices of affective-relational development in early infancy. From a methodological point of view, this concept relies on the Lausanne Trilogue Play (LTP) observational paradigm. Objectives: The aim of this study was to investigate a) the psychometric characteristics of the administration and coding of the pre-natal and post-natal LTP procedure; b) the patterns of stability and/or change in triadic family interactions from pregnancy till the baby’s 9th month. Method: 70 non-referred primiparous families were recruited at child-birth courses of two North-Italian hospitals. Observational data were collected at time 1 (7th month of pregnancy) with the prenatal LTP, and at postnatal times 2 and 3 (when the baby was 4 and 9 months old). Results: The collected data show good reliability of the LTP coding system and a consistent factorial structure in line with previous validation studies (Carneiro et al., 2006; Favez et al., 2006). The applied multilevel analysis highlights an improvement in triadic interactive competences during the first year. Findings show a linear relationship between time and quality of family interactions whereby competences improve by 2.35 points at each observational phase. Family interactions are not stable: rather, the quality of triadic family interactions increases from pregnancy to parenthood. Conclusion: The adults’ interactive abilities during pregnancy represent an interactive matrix for the construction of early family relationships and may be considered predictive of the child’s development of early triadic interactive abilities during the first months of life.