Breastfeeding is the ideal feeding for the newborn. The success of the initiation and maintenance of breastfeeding can be influenced by different factors, as breastfeeding self-efficacy. Brief Motivational Intervention (BMI) is a form of collaborative guidance, person-centered approach aimed at strengthening the motivation to adopting healthy initiatives and can increase the self-efficacy.

The hypothesis is that an BMI to promote breastfeeding, during immediate postpartum plus telephone support at the first and third postpartum months, will significant increase in the adherence and duration of breastfeeding compared with the habitual education action applied at the same time. Also, the BMI will increase the breastfeeding self-efficacy of the particpants, and this breastfeeding self-efficacy will be a mediator of the effect between the IMB and the breastfeeding duration.

The general self-efficacy of the participants will change the size of the effect of BMI.

Inclusion Criteria:

• All women with term gestations who have given birth healthy newborns by vaginal delivery at the hospital .who agree to participate in the study by signing informed consent, will be includes in the study

Exclusion Criteria:

• Mothers who, by medical indication or own decision, do not initiate breastfeeding in the first hour of the newborn's life.
• Mother of children who require admission to the neonatal unit.
• Women with a previously diagnosed psychiatric disorder.
• Neurological or cognitive impairment that impedes the evaluation and the BMI
• Resident status that prevents correct follow-up of patients (eg. residence outside Spain).
• Women with language or communication barriers