Ankyloglossia and Breastfeeding

A prospective observational cohort study will be conducted. Mother-infant dyads will be recruited during the newborn's first 72 hours of life, during the hospital admission for childbirth at the University Hospital of Guadalajara.

The presence of ankyloglossia will be assessed using the TABBY tool during the first 72 hours of life. Newborns will be classified into two cohorts according to the presence or absence of ankyloglossia. The planned sample size is 146 mother-infant dyads: 73 newborns with ankyloglossia and 73 newborns without ankyloglossia.

Non-probability consecutive sampling will be used. For each newborn with ankyloglossia included in the study, one newborn without ankyloglossia will be selected from among the next newborns assessed who meet the inclusion criteria and whose parents provide informed consent.

The study will not assign interventions or modify routine clinical care. The performance of frenotomy and the provision of individual breastfeeding counselling will depend on the clinical assessment and the decisions made by the healthcare professionals responsible for the participants' care. These procedures will be recorded to analyse their possible association with breastfeeding outcomes.

The initial assessment of ankyloglossia using TABBY and breastfeeding effectiveness using LATCH will be performed during the first 72 hours of life. The dyads will be followed up between 5 and 15 days, between 30 and 40 days, and at 4 and 6 months of life. Information will be obtained from clinical assessments, electronic health records and, when necessary, telephone interviews.

Inclusion criteria

• Mother-infant dyads recruited during the newborn's first 72 hours of life, during the hospital admission for childbirth at the University Hospital of Guadalajara.
• Singleton pregnancy.
• Gestational age at birth between 37 weeks and 41 weeks and 6 days.
• Maternal intention to provide exclusive or mixed breastfeeding.
• Written informed consent provided by the parent or legal guardian.

Exclusion criteria

• Birth outside the University Hospital of Guadalajara.
• Preterm birth (<37 weeks of gestation).
• Fetal or neonatal pathology diagnosed before or after birth.
• Admission to the neonatal unit after birth or during the hospital stay.
• Any contraindication to breastfeeding.
• Language barriers preventing communication in Spanish with the parents or legal guardians.
• Withdrawal of informed consent.
• Loss to follow-up.