How Tongue Tie Is Diagnosed: Appearance, Function & Symptoms

Seeing a frenulum does not mean your baby has a tongue tie or lip tie. All humans have multiple frenula. What matters is whether that tissue is restrictive.

A complete, accurate diagnosis includes three components:

1. Appearance

Does the frenulum appear short, tight, thick, or restrictive?Providers may use grading tools to describe the anatomy—but grading alone does not determine clinical significance.

2. Function

The most important factor: Can the tongue or lip move normally?During an evaluation, providers look for:

• Tongue lift

• Tongue extension

• Cupping and peristaltic motion

• Lateralization

• Lip mobility and flanging

• Ability to maintain suction

  
  

3. Symptoms

Appearance and restricted movement only matter if they cause symptoms, such as:

• Poor milk transfer

• Parent nipple pain

• Inefficient feeding

• Reflux or aerophagia

• Weight gain concerns

  
  

This three-part approach — appearance + function + symptoms — is widely supported in the clinical lactation and medical literature.

Why Functional Assessment Matters

Some babies have visually dramatic frenula but no feeding issues at all. Others have subtle or “posterior” restrictions that significantly impair tongue motion. Because of this variability, function must always guide diagnosis, not appearance alone.

A collaborative approach involving lactation professionals and skilled medical providers gives families the most accurate and helpful plan forward.

Sources

Baeza C et al. Incidence and Prevalence of Tongue Tie. Clinical Lactation. 2017.

Geddes DT et al. Frenulotomy for Breastfeeding Infants With Ankyloglossia. Pediatrics. 2008.

Ghaheri B et al. Breastfeeding Improvement Following Tongue Tie and Lip Tie Release. Laryngoscope. 2016.

Messner A et al. Clinical Consensus Statement on Ankyloglossia in Children. 2020.

Watson Genna C. Supporting Sucking Skills in Breastfeeding Infants. 2016.