Tongue-Tie and Breastfeeding: What New Research Tells Families About Checking, Treating and Caring for a Newborn's Tongue

A plain-language guide to four 2025 studies from Portugal, Finland, Spain and an international review of the research on tongue-tie release

A small band of tissue and a big question for new parents

Tongue-tie is common, affecting roughly one newborn in eight in recent European studies. It can make breastfeeding painful for some mothers, but many babies with a tongue-tie feed well. New research from 2025 suggests that careful checking matters more than the look of the tongue, that cutting the tie brings uncertain benefit, and that follow-up exercises may help.

Under every baby's tongue is a thin fold of tissue called the frenulum. In some babies it is shorter, thicker or attached closer to the tip of the tongue than usual, which can stop the tongue from lifting and stretching forward freely. Doctors call this ankyloglossia; most people call it tongue-tie. Because a baby uses the tongue to cup the nipple and draw milk during breastfeeding, parents and health workers naturally wonder whether a tongue-tie is behind a painful or difficult feed. The answer, as four studies published in 2025 show, is "sometimes, but not always" [1], [2], [3], [4].

How tongue-tie became such a talked-about problem

Tongue-tie is not new, but the attention it receives is. Over the past 20 years, the number of babies diagnosed and treated has risen dramatically in several countries. In the United States, hospital diagnoses rose by up to 834% between 1997 and 2012, and similar increases in the simple snip to release the tie, called a frenotomy, were seen in Australia and Canada [5], [6], [7]. Experts think much of this rise reflects changing habits among health professionals rather than more babies actually being born with the condition [2].

Part of the problem is that there has never been one agreed way to decide whether a tongue-tie needs treatment. Different checklists look at different things, some focusing on how the tissue looks and others on how the tongue moves, and they give very different answers about how common tongue-tie is [8]. Professional groups, including the American Academy of Pediatrics, have noted that clear guidelines are still missing [9]. Families have therefore often received conflicting advice from different health workers. When health services in one region of New Zealand combined better breastfeeding support with more careful referral, the number of frenotomies fell without any harm to breastfeeding [10]. That experience raised a question the 2025 studies set out to answer: how can we tell which babies genuinely need help?

Four studies, four pieces of the puzzle

The four studies each looked at a different part of the journey, from first check to aftercare.

In Porto, Portugal, a children's dentist who is also an expert breastfeeding consultant examined 501 healthy newborns at São João University Hospital in their first few days of life [1]. The examiner checked each baby's tongue with a well-known checklist and asked mothers about feeding and nipple pain.

In Oulu, Finland, a research programme called the Lingual Frenulum in Newborn Infants (LINNE) project checked 556 babies born at Oulu University Hospital, the only maternity hospital in its area [2]. Each baby was examined separately by a doctor and a midwife using a picture-based checklist, and each mother filled in a short questionnaire about how breastfeeding felt. The researchers wanted to know whether this combined score was reliable.

A team of researchers pulled together 55 earlier studies of tongue-tie release in young children, a type of study called a systematic review, and combined the numbers from six of them, known as a meta-analysis, to see whether cutting the tie improves breastfeeding [3].

At Hospital del Mar in Barcelona, Spain, doctors and nurses followed 212 newborns who had a frenotomy because their mothers had pain or trouble with latching [4]. Parents were shown a set of simple tongue exercises to do at home for two weeks, and the babies were checked again after 10 to 15 days to see whether the tissue had grown back together, which is called readhesion.

What the researchers found

Tongue-tie turned out to be common. In Porto, about 14 in every 100 newborns had a tongue-tie, and in Oulu about 13 in every 100 babies met the criteria for early treatment [1], [2].

In Porto, having a tongue-tie did not stop babies from being exclusively breastfed while in hospital; overall about 71 in every 100 babies were fed only breast milk, and the rate was much the same whether or not the baby had a tongue-tie [1]. What tongue-tie did change was comfort. Mothers of babies with a tongue-tie were about one and a half times as likely to have sore nipples during feeds. Other things mattered more for exclusive breastfeeding, such as starting to breastfeed in the first hour after birth and avoiding bottles, dummies and nipple shields where possible.

In Oulu, the picture checklist was good at picking out the babies who needed treatment, and midwives used it well as well as doctors [2]. But when two trained people examined the same baby, they agreed only moderately often. Babies' mouths are small and they do not always cooperate, and the researchers suggested checking an alert baby who is just starting to feed. A family history of tongue-tie made it more likely that a baby would need treatment, but many babies who needed help had no such family history.

The review of earlier research gave a mixed picture [3]. At first glance, the combined numbers suggested that cutting the tie helped breastfeeding. But this result depended almost entirely on one older study, and when that study was set aside, the benefit disappeared [11]. The reviewers found that most studies used different checklists and relied on mothers' own reports, so they could not recommend cutting every tongue-tie. They concluded that the procedure may help selected babies with real feeding problems.

In Barcelona, about one in three babies had some regrowth of the tissue two weeks after frenotomy, but only about one in six still had feeding symptoms, and about one in seven had the procedure repeated [4]. Families who did the exercises as advised had less regrowth: about 28 in every 100 babies, compared with about 73 in every 100 among the small group of families who did no exercises. Boys were more likely than girls to have regrowth. Encouragingly, at the two-week check fewer than one in five mothers still had nipple pain, and 95 in every 100 babies were still being breastfed.

What this means for your family

If breastfeeding is going well and comfortable, a tongue-tie that someone notices may simply need watching, not treating. The Portuguese study suggests many babies with a tongue-tie feed well in the first days [1].

If breastfeeding hurts or your baby struggles to latch, the first step is usually a careful feeding assessment by someone skilled in breastfeeding support. Positioning, latch and early feeding routines often make a real difference. A tongue check using a recognised checklist can then show whether a tongue-tie might be part of the picture [2].

If a frenotomy is offered, it is reasonable to ask how the decision was made, what pain relief or comfort measures will be used, and what follow-up is planned. Gentle, non-drug comfort measures for brief newborn procedures are described in another In[Neo]Sight article on easing newborn pain (Non-pharmacological neonatal pain relief). Good care includes checking for problems afterwards, as a national study in New Zealand has done for frenotomy [12].

After a frenotomy, ask whether tongue exercises are recommended and how often to do them. The Barcelona results suggest that doing them regularly may reduce regrowth, although this has not yet been tested in a trial where some families do exercises and others do not [4]. A check-up about two weeks later is sensible. If the tissue has partly regrown but feeding is going well, a second procedure is usually not needed.

It is also worth remembering that the evidence is still developing. It is perfectly reasonable to feel uncertain, to ask questions and to seek a second opinion before deciding.

What researchers are working on next

Several important studies are under way. The Finnish LINNE team is running a randomised trial of tongue-tie treatment, in which babies are allocated by chance to different approaches, which should show more clearly who benefits [2]. The Barcelona team is running a trial comparing families who do the exercises with families who do not [4]. Researchers also want to agree on a single, reliable way of checking babies' tongues, to test it in premature babies and in neonatal intensive care units [2], and to follow families for months rather than days [3]. A 2025 study in slightly older babies also found less regrowth among families who kept up stretching exercises, adding to the case for well-designed trials [13].

A balanced way forward

Tongue-tie is common, and it can make breastfeeding painful for some mothers, but it is not a reason for alarm and not every tongue-tie needs cutting. The newest research points families and health workers toward the same approach: look first at how feeding is going, check the tongue carefully with a recognised tool, reserve frenotomy for babies whose feeding problems are likely linked to the tie, and plan simple aftercare and a follow-up visit.

References

  1. Morgado Dias J, Abanto J, Correia Pinto J, Areias C, Soares H. Prevalence of Ankyloglossia in Portuguese Newborns and Its Effect on Exclusive Breastfeeding and Maternal Nipple Pain During Postpartum Hospitalization. J Pediatr Clin Pract. 2026;19:200195. doi:10.1016/j.jpedcp.2025.200195 ↩
  2. Lehtinen A, Lohi V, Aitamurto S, Aikio O. Tongue-tie diagnosis using the Lingual frenulum in newborn infants (LINNE) -scoring: A validation study. PLoS One. 2025;20(12):e0338491. doi:10.1371/journal.pone.0338491 ↩
  3. Jerez Delgadillo G, Zlatar Rojas J, Muñoz MA, Luque-Martínez I. Frenectomy for ankyloglossia in children under five: a systematic review and meta-analysis on breastfeeding outcomes. Int Breastfeed J. 2025;20(1):81. doi:10.1186/s13006-025-00773-x ↩
  4. Valle-Del Barrio B, Maya-Enero S, Prat-Ortells J, López-Vílchez MÁ, Candel-Pau J. Readhesion of Tongue-Tie Following Neonatal Frenotomy: Incidence and Impact of Postoperative Exercises in a Prospective Observational Study. Children (Basel). 2025;12(8):971. doi:10.3390/children12080971 ↩
  5. Walsh J, Links A, Boss E, Tunkel D. Ankyloglossia and Lingual Frenotomy: National Trends in Inpatient Diagnosis and Management in the United States, 1997-2012. Otolaryngol Head Neck Surg. 2017;156(4):735-740. doi:10.1177/0194599817690135 ↩
  6. Kapoor V, Douglas PS, Hill PS, Walsh LJ, Tennant M. Frenotomy for tongue-tie in Australian children, 2006-2016: an increasing problem. Med J Aust. 2018;208(2):88-89. doi:10.5694/mja17.00438 ↩
  7. Lisonek M, Liu S, Dzakpasu S, et al. Changes in the incidence and surgical treatment of ankyloglossia in Canada. Paediatr Child Health. 2017;22(7):382-386. doi:10.1093/pch/pxx112 ↩
  8. Cruz PV, Souza-Oliveira AC, Notaro SQ, et al. Prevalence of ankyloglossia according to different assessment tools: A meta-analysis. J Am Dent Assoc. 2022;153(11):1026-1040.e31. doi:10.1016/j.adaj.2022.07.011 ↩
  9. Thomas J, Bunik M, Holmes A, et al. Identification and Management of Ankyloglossia and Its Effect on Breastfeeding in Infants: Clinical Report. Pediatrics. 2024;154(2):e2024067605. doi:10.1542/peds.2024-067605 ↩
  10. Dixon B, Gray J, Elliot N, Shand B, Lynn A. A multifaceted programme to reduce the rate of tongue-tie release surgery in newborn infants: Observational study. Int J Pediatr Otorhinolaryngol. 2018;113:156-163. doi:10.1016/j.ijporl.2018.07.045 ↩
  11. Ballard JL, Auer CE, Khoury JC. Ankyloglossia: assessment, incidence, and effect of frenuloplasty on the breastfeeding dyad. Pediatrics. 2002;110(5):e63. doi:10.1542/peds.110.5.e63 ↩
  12. Hale M, Mills N, Edmonds L, et al. Complications following frenotomy for ankyloglossia: A 24-month prospective New Zealand Paediatric Surveillance Unit study. J Paediatr Child Health. 2020;56(4):557-562. doi:10.1111/jpc.14682 ↩
  13. Miller JE, Chung HR, Marshall CR, et al. Outcomes of stretching exercises after lingual frenotomy in infants: A prospective, interventional study. Int J Pediatr Otorhinolaryngol. 2025;191:112280. doi:10.1016/j.ijporl.2025.112280 ↩