Patients and methods: a prospective multicenter (Clínica Alemana de Santiago and Hospital San José) cohort study with comparative and explanatory elements. The study will comprise four periods (during hospitalization and at 2, 6 and 12 months of corrected gestational age). An experimental and a control group will be randomized when a MLP newborn is hospitalized. The experimental group will be composed of late and moderately late preterm infants (MLP) born between 32 to 366 weeks of pregnancy, who will be verbally intervened by the treating physician in outpatient well child consultations at 2, 6 and 12 months corrected age, trough interactive guidance with the aim of potentiating the interaction of the infant with the parents to reduce sustained social withdrawal. Likewise, an analysis of both institutions (Clinica Alemana de Santiago and Hospital San Jose) will be performed to assess the differences between them. The tools that will be applied are the ADBB scale, as dependent variable; the Edinburgh Post-natal Depression Scale to be applied to parents; the Modified Perinatal Post-Traumatic Stress Disorder Questionnaire and the Revised Impact of Events Scale. During the hospitalization of MLP infants, the painful and invasive procedures to which the infant is subjected will be quantified, as well as neonatal pain, hours of skin-to-skin contact, breastfeeding and parental visits. Results relevance and applicability: Efficient early detection and intervention in infants with sustained social withdrawal behavior is essential to prevent problems in their social and emotional development. Assessing sustained social withdrawal using a standardized and simple scale like the ADBB Scale will allow for monitoring the infant and implementing cost-effective interventions that will benefit him, his family and the society. Identifying the risk groups, i.e. with difficulties in the social and emotional development area, will allow us to optimize the follow-up and integral support programs according to the infants' health needs as well as to establish a care standard.