Tongue-Tie and Bottle-Feeding: How to Tell If It’s the Cause

Over the past several years, there has been a significant increase in the number of babies diagnosed with tongue-tie (ankyloglossia), particularly among babies experiencing breastfeeding or bottle-feeding difficulties.

Tongue-tie was once an under-recognised cause of breastfeeding problems. However, it is now frequently diagnosed in babies with unsettled or distressed feeding behaviour, even when other non-physical causes have not been fully assessed.

In my clinical work with babies experiencing feeding aversion, I often see tongue-tie procedures recommended without a thorough review of feeding history, feeding behaviour, and environmental or behavioural factors that can significantly affect feeding. In many cases, these assessments alone would rule out tongue-tie as the primary cause.

What is tongue-tie (ankyloglossia)?

Tongue tie is relatively common. Many babies, children, and adults have a tongue-tie to varying degrees. For the vast majority, it causes no ill effects on feeding or speech.

Just as tongue tie is common, so too are infant feeding problems. It’s estimated that 25 to 45 percent of normal developing babies, with or without a tongue-tie, experience feeding problems. The fact that a baby has a tongue-tie and also feeding difficulties does not prove causation.

Your health professional or pediatric dentist can see if your baby has one of 4 grades of tongue-tie. However, without knowledge of reasons and solutions for behavioral infant feeding problems, such as feeding aversion due to being repeatedly pressured to feed, faulty or inappropriate feeding equipment, poor positioning or latch, misinterpretation of infant feeding cues, forceful or delayed letdown while breastfeeding, and severe sleep deprivation affecting feeding – health professionals in general don’t ask relevant questions to check for these problems, and instead make assumptions that the cause is physical. At some point, generally after acid-suppressing medications and hypoallergenic formula have failed to improve the situation (which will be the case for a behavioral feeding problem), a tongue-tie snip or laser procedure may be recommended as part of a process of systematically eliminating physical causes.

Any diagnosis that excludes an assessment of the various behavioral reasons for a baby’s troubled feeding behavior has the potential to be way off the mark. Exposing a baby to minor trauma associated with having her tongue-tie snipped or lasered (plus weeks of stretching to prevent the wound from reattaching), based solely on a vague hope that it might help, is likely to cause more harm than good.

A small percentage of babies with severe tongue-tie that tethers the bottom of the tongue’s tip to the floor of the mouth, and thus restricting movement of the tongue, may benefit from having a tongue-tie division procedure. For most, it will make no difference to their feeding behavior. For others, it can further complicate the situation by triggering or worsening a feeding aversion. Hence, if you’re concerned about tongue-tie affecting your baby’s feeding, it may be prudent to do your own assessment rather than rely solely on assumptions made by your health professional.

A small number of babies with severe tongue-tie that significantly restricts tongue movement may benefit from a tongue-tie division procedure, particularly when breastfeeding difficulties are clearly linked to restricted tongue function and other causes have been ruled out.

How to tell if tongue-tie is affecting feeding

There are ways you can tell if your baby’s tongue-tie is affecting feeding or not. Below is a brief guide on how you might be able to rule out or rule in tongue-tie, and how this compares to a feeding aversion.

1) Tongue-tie is FAR more likely to affect breastfeeding than bottle-feeding due to the different way a baby’s tongue moves for each feeding method. While breastfeeding, Baby’s tongue needs to be free to roll in a wave-like action to ‘milk’ the mother’s milk ducts. While there is some degree of suction involved, effective breastfeeding is mostly achieved by Baby’s tongue compressing the mothers’ milk ducts, which then pushes milk into baby’s mouth. Whereas, while bottle-feeding, a baby’s tongue cups the nipple as she sucks. Movement of her tongue while bottle-feeding is minimal.

A behavioral feeding aversion can affect both breast- and bottle-fed babies.

2) Tongue-tie often runs in families and is thought to be more common in boys than girls.

3) Tongue-tie is a condition that is present at birth. And therefore, in the case of a bottle-fed baby, feeding difficulties would be evident from the time she first started to bottle-feed. In the case of a breastfed baby, a tongue-restriction problem may only become evident after a mother’s oversupply of breastmilk settles, at which time baby needs to actively feed rather than be a passive recipient of milk spraying into her mouth.

A behavioral feeding aversion typically develops around the age of 6 to 8 weeks and worsens as Baby matures. See Chapter 3 in my book, ‘Your Baby’s Bottle-feeding aversion’ for further description of how a behavioral feeding aversion first presents and develops.

4) Tongue-tie and other structural and functional impairments that negatively impact on feeding will affect ALL feeds, both awake and drowsy/sleepy feeds.

It’s very common for babies with a behavioral feeding aversion to appear like she is having feeding difficulties while awake and during the day, but feed well at night while relaxed or in a drowsy/sleepy state.

5) There is a difference between a baby ‘having difficulty feeding’ and ‘not wanting to feed’.

Conflicted feeding behavior, which is commonly displayed by babies who are averse to feeding, is often mistakenly interpreted as the baby experiencing pain while feeding, or having trouble remaining latched to the breast, or having an uncoordinated suck.

When tongue-tie is unlikely to be the cause 

Tongue-tie is unlikely to be the cause of feeding difficulties when a baby is able to feed effectively in some situations but not others, or when the pattern of feeding behaviour does not fit with what would be expected from a true mechanical restriction.

From a clinical perspective, tongue-tie is less likely to be responsible when:

• Feeding difficulties are inconsistent, such as when a baby feeds poorly while awake but feeds well when drowsy or asleep. A structural restriction would affect feeding at all times.

• Feeding problems began weeks after birth, rather than being present from the first feeds. Tongue-tie exists from birth and, if significant, would be expected to interfere with feeding from the outset, particularly with bottle-feeding.

• Bottle-feeding is more problematic than breastfeeding, despite appropriate teat flow and positioning. Tongue-tie more commonly interferes with breastfeeding mechanics than bottle-feeding.

• Weight gain is adequate or above average, despite distressed or resistant feeding behaviour. Babies whose feeding is limited by tongue restriction typically struggle to transfer milk efficiently.

• Feeding behaviour shows conflict or avoidance, such as pulling away, arching, crying at the sight of the bottle or breast, or feeding only under specific conditions. These patterns are more consistent with a feeding aversion than with a physical restriction.

In many babies, feeding difficulties are functional or behavioural rather than structural, particularly where feeding pressure, repeated attempts to coax intake, unsuitable feeding equipment, or chronic fatigue are present. In these cases, addressing the behavioural drivers of feeding difficulty is more likely to improve feeding than a surgical procedure.

For this reason, tongue-tie should be considered only after a careful assessment of feeding history, feeding behaviour, growth, and the circumstances under which feeding improves or worsens. Without this broader assessment, there is a risk of attributing feeding difficulties to tongue-tie when it is not the underlying cause.

When to see a doctor

While many feeding difficulties are behavioural or functional, it is important for babies with feeding concerns to be medically assessed to rule out underlying health issues.

Seek medical advice if your baby:

• Is gaining weight poorly or losing weight

• Has persistent vomiting, blood or mucus in stools, or ongoing diarrhea

• Shows signs of pain or distress during every feed, both awake and drowsy

• Has breathing difficulties, frequent coughing, choking, or colour changes during feeds

• Has difficulty feeding from birth, with no periods of comfortable or effective feeding

• Appears lethargic, unwell, or developmentally off track

A medical assessment can help exclude conditions that require treatment. If no medical cause is identified, further assessment of feeding behaviour, feeding history, and caregiving practices is often helpful before considering invasive procedures.

Written by Rowena Bennett

About Rowena

Rowena Bennett (RN, RM, CHN, MHN, IBCLC) is a leading infant-feeding and sleep specialist and author of several books on infant feeding and behaviour, including the widely acclaimed “Your Baby’s Bottle-Feeding Aversion: Reasons & Solutions". With over three decades of clinical experience across child health, midwifery, mental health, and lactation, she has helped thousands of families worldwide understand and resolve complex feeding challenges through her evidence-based, baby-led approaches.

© Copyright Rowena Bennett 2026. All rights reserved. Permission from the author must be obtained to reproduce all or any part of this article.