The structures and functions of a newborn baby’s and young infant’s mouth can affect the life-long processes of feeding and speech. While many parents (and professionals) may be unaware, problems can begin to arise in utero and in the first weeks to months of life. However, through parent and professional education, there are ways to keep a baby’s mouth development “on track” beginning at birth. This article describes and discusses face, mouth, and throat characteristics in newborn and young babies, so parents and professionals can identify typical vs. atypical anatomy and physiology.

Face, Mouth, and Throat Characteristics in Newborns and Early Infancy

Newborns, children, and adults share some similar facial characteristics if their structures have developed appropriately. This includes a nice broad horizontal eye area (approximately the width of one eye times 5), the center corners of the eyes lining up with the widest part of the nose, a relatively straight lip line, and a nose to philtrum angle that is 90 to 110 degrees (Boshart, 1999).

However, newborns have eleven unique mouth and throat characteristics that warrant discussion.

A newborn has:

  • Mouth and throat structures in very close proximity
  • Limited open space within the mouth and throat areas
  • A small, slightly retruded (pulled back) lower jaw
  • A wide “U” shaped palate
  • A flexible/moveable palate
  • Nose breathing
  • A tongue that fills the mouth at rest
  • A deeply cupped tongue when suckling
  • Gums that enlarge to assist with the latch
  • Ample sucking pads in the cheeks
  • Relatively horizontal positioning of the Eustachian tubes

(Bahr, 2001, 2010, 2015; Coryllos, Genna, & Salloum, n.d.; Geddes, Kent, Mitoulas, & Hartmann, 2008; Morris, 1985; Morris & Klein, 2000; Oetter, Richter, & Frick, 1995; Page, 2003b; Upledger & Vredevoogd, 1983; Upledger, 1996)

Mouth and Throat Structures Close/Limited Space

A newborn’s mouth and throat structures are close together, so there is limited open space within the mouth and throat areas. This helps typically developing, full-term newborns to safely feed and swallow. As the infant grows and develops feeding skills, there is increasing open space within the infant’s mouth and throat areas.

Additional resources:

Oral Motor Assessment and Treatment: Ages and Stages

Therefore, the mouth and throat areas of a newborn are different from a three or six- month old baby secondary to growth. Feeding therapists (e.g., lactation consultants, speech-language pathologists, occupational therapists, orofacial myofunctional therapists, etc.) must keep these changes in mind when helping parents develop feeding programs.

Retruded Lower Jaw

Newborn babies have small, slightly retruded (pulled back) lower jaws (mandibles) which are approximately 30 percent of adult size at birth (Page, 2003a). There is significant jaw growth in the first year of life (Enlow, 1982; Page, 2003b; Van der Liden, 1986). By six months parents will notice their baby’s lower jaw beginning to line up with the baby’s philtrum (area above the upper lip) and bridge of the nose when viewed from the side (i.e., profile). Jaw growth is facilitated via appropriate feeding and mouth development activities (e.g., breastfeeding; age appropriate food and liquid introduction, appropriate mouthing of hands, fingers, and mouth toys; etc.).

“U”: Shaped Palate

The newborn’s palate (roof of the mouth) has a wide “U” shape and is approximately ¾ to 1 inch wide (Page, 2003b) from side-to-side across midline (i.e., 50 percent of adult width). The palate is flexible and moveable at birth but will harden over time. Palatal development and shape are significantly influenced by the placement of the baby’s tongue at rest and during breastfeeding. The baby’s tongue should rest lightly suctioned against the roof of the mouth, and the mother’s breast should be drawn deeply into the baby’s mouth during breastfeeding to help maintain the palate’s broad “U” shape (Page, 1999).

Flexible Palate

However, if a baby has an open-mouth posture at rest or uses a pacifier excessively, the baby’s tongue cannot do its job in keeping the palate’s shape. Additionally, bottle feeding is a very different process than breastfeeding and does not help to maintain the palate’s shape (Gomes, Trezza, Murade, & Padovani, 2006; Jacinto-Goncalves, Gaviao, Berzin, de Oliveira, & Semeguini, 2004). Bottle feeding is a medicalized way of feeding a human infant. According to the American Academy of Pediatrics (2012, p. e827), “breastfeeding and human milk are the normative standards for infant feeding and nutrition.”

Nose Breathing

If the palate’s shape becomes high and narrow, this will impact the shape and size of the nasal area as the palate is the floor of the nasal cavity. Small nasal areas can make nose breathing difficult and nasal passages hard to clear leading to upper respiratory issues. Nose breathing is needed for effective suck-swallow-breathe synchrony used in breast and bottle feeding as well as efficient oxygenation of the blood for all life processes (Alexander, 1987; Gray, 1980; Lundberg, Farkas-Szallasi, Weitzberg, Rinder, Lidholm, Anggaard, Hokfelt, Lundberg, & Alving, 1995; McCann, Licinio, Wong, Yu, Karanth, & Rettorri, 1998; Northrup, 2001, 2005; Page, 2003a & b; Schedin, Norman, Gustafsson, Herin, & Frostell, 1996).

Tongue Fills the Mouth at Rest

As previously mentioned, the newborn’s tongue fills the mouth at rest to help maintain the palate’s broad shape. The tongue should be mobile and not tied nor restricted. Tongue and other oral restrictions may be genetic (Acevedo, da Fonseca, Grinham, Doudney, Gomes, de Paula, & Stanier, 2010; Han, Kim, Choi, Lim, & Han, 2012; Klockars & Pitkaranta, 2009). Clinically, it seems that babies with tongue ties may also have lip or buccal (cheek) ties. These ties are currently referred to as tethered oral tissues.

Tongue tie (i.e., ankyloglossia frequently caused by a short, thick lingual frenum) usually restricts the tongue from coming over the lower gum during suckling. This can significantly impact feeding and may cause the baby to use compensatory, abnormal tongue and jaw movements during breast or bottle feeding such as tongue humping, bunching, and/or thrusting as well as chomping on the breast or bottle for stability. (Geddes, Langton, Gollow, Jacobs, Hartmann, and Simmer, 2008; Haham, Marom, Mangel, Botzer, & Dollberg, 2014). Lip and/or cheek ties may affect a baby’s latch as lips and cheeks work together for a symmetrical lip latch on the breast or bottle (Kotlow, 2013). The degree of tongue, lip, or cheek tethering determines their impact on feeding and whether a release or revision is needed.

Deeply Cupped Tongue

A newborn’s tongue is deeply cupped during reflexive suckling (a response with which typical babies are born). During suckling, the tongue has a “distinctive, rhythmical, backward-forward stripping movement that helps draw liquid into the mouth” (Morris & Klein, 2000, p. 77). “Breast-feeding is a dynamic process, which requires coupling between periodic motions of the infant’s jaws, undulation of the tongue, and the breast milk ejection reflex” (Elad, Kozlovsky, Blum, Laine, Po, Botzer, Dollberg, Zelicovish, & Sira, 2014, p. 5230). While the movements for breast and bottle feeding appear similar, there are differences between these processes.

Enlarged Gums

During the feeding process, the newborn’s gums reportedly enlarge to assist with the latch (Montagu, 1986). This enlargement (which is likely due to increased blood supply to the area) reportedly subsides between 3 and 6 months of age as the baby uses a volitional 3-dimentional suck in place of the reflexive suckle. In the 3-dimentional suck, the tip and sides of the tongue move upward and the lips pucker. The tongue is still cupped but not as deeply cupped as that of the newborn. Tongue cupping and tongue tip elevation are essential for the development of a mature swallowing pattern.

Buccal Sucking Pads

Full-term typically developing newborns are also born with buccal fat pads (commonly called sucking pads). These develop toward the end of pregnancy when other fat is developing on a baby’s body, so premature babies do not develop them and near-term babies may have thin ones. Sucking pads are balls of fat in a baby’s cheeks that help keep the cheeks against the gums, so the baby can attain appropriate intraoral pressure during feeding. They supply lateral stability in the mouth until the baby’s cheek muscles (particularly the buccinators) gain control of the process between 4 and 6 months. At this time, the baby engages the 3-dimentional suck and chews on appropriate mouth toys and safe first foods while the sucking pads shrink and the cheek muscles become increasingly active.

Horizontal Eustachian Tubes

The Eustachian tubes (which originate at the back of the nasopharynx and end in the middle ear space) are relatively horizontal in newborns. This is one reason babies’ bodies are positioned at a 45 degree (or greater) angle when bottle fed. If a baby is bottle fed lying down (supine), there is greater opportunity for liquid to enter the Eustachian tubes than if a baby is feed upright (NIH, 2014). Bottle feeding also seems to involve a different set of pressures than breastfeeding. In breastfeeding, the pressures in the oral, nasal, and pharyngeal systems seem to be equalized. Breastmilk also reportedly contains some antibacterial qualities that will likely protect the baby if breastmilk should enter the Eustachian tubes. Therefore, a variety of breastfeeding positions may be safely used to feed a baby. It is also well-known that breastfed babies have fewer middle ear problems and upper respiratory issues than bottle fed babies (Aniansson, Alm, Andersson, Hakansson, Larsson, Nylen, Peterson, Rigner, Svanborg, Sabharwal, et al., 1994; Watkins, Leeder, & Corkhill, 1979).


It is important that parents and professionals have a good understanding of newborn and early infant anatomy, physiology, growth, and development, so they can apply and encourage the best possible mouth, feeding, and vocal development practices in babies and young children. In this article, we touched on newborn and early infant anatomy and physiology. However, the processes of feeding, oral play, and early vocal/speech development are overlaid on this anatomy and physiology, and these processes develop significantly during the first two years of life beginning at birth. Information on feeding, mouth development activities, and early speech development can be found in books by Morris & Klein (2000), Bahr (2010), and others. To date, there appears to be only one longitudinal study on feeding and pre-speech skills by Morris (1978, revised 2003). Therefore, research is required.

Links of Interest

  1. Nobody Ever Told Me (or my Mother) That!: Everything from Bottles and Breathing to Healthy Speech Development
  2. Oral Motor Assessment and Treatment: Ages and Stages
  3. For more information, visit her website: 


  1. Acevedo, A. C., da Fonseca, J. A., Grinham, J., Doudney, K., Gomes R. R., de Paula, L. M., & Stanier, P. (2010). Autosomal-dominant ankyloglossia and tooth number anomalies. Journal of Dental Research, 89(2), 128-132.
  2. Alexander, R. (1987). Oral-motor treatment for infants and young children with cerebral palsy. Seminars in Speech and Language 8(1), 87-100.
  3. American Academy of Pediatrics. (2010). Breastfeeding and the use of human milk. Pediatrics, 129(3), E827-e841.
  4. Aniansson, G., Alm, B., Andersson, B., Hakansson, A., Larsson, P., Nylen, O., Peterson, H., Rigner, P., Svanborg, M., Sabharwal, H., et al. (1994). A prospective cohort study on breast-feeding and otitis media in Swedish infants. The Pediatric Infectious Disease Journal, 13(3), 183-188.
  5. Bahr, D. (2015). Everything you need to know about a baby’s mouth for good feeding, speech, and mouth development. Las Vegas, NV: Ages and Stages® E-Course.
  6. Bahr, D. (2010). Nobody ever told me (or my mother) that! Everything from bottles and breathing to healthy speech development. Arlington, TX: Sensory World.
  7. Bahr, D. C. (2001). Oral motor assessment and treatment: Ages and stages. Needham Heights, MA: Allyn & Bacon.
  8. Boshart, C. (1999). Oral-Facial illustrations and reference guide. Temecula, CA: Speech Dynamics.
  9. Coryllos, E., Genna, C. W., & Salloum, A. C. (n. d.). Congenital tongue-tie and its impact on breastfeeding. American Academy of Pediatrics: Section on Breastfeeding. Accessed August 24, 2009
  10. Elad, D., Kozlovsky, P., Blum, O., Laine, A. F., Po, M. J., Botzer, E., Dollberg, S., Zelicovish, M., & Sira, L. B. (2014). Biomechanics of milk extraction during breast feeding. Proceedings of the National Academy of Sciences, 111(14), 5230-5235.
  11. Enlow, D. (1982). Handbook of facial growth. New York, NY: W. B. Saunders Book Publishers.
  12. Geddes, D. T., Langton, D. B., Gollow, I., Jacobs, L. A., Hartmann, P. E., & Simmer, K. (2008). Frenulotomy for breastfeeding infants with ankyloglossia: Effect on milk removal and sucking mechanism as imaged by ultrasound. Pediatrics, 122(1), e188-e194.
  13. Geddes, D. T., Kent, J. C., Mitoulas, L. R., & Hartmann, P. E. (2008). Tongue movement and intra-oral vacuum in breastfeeding infants. Journal of Early Human Development, 10, 1016.
  14. Gomes, C. F., Trezza, E. M., Murade, E. C., & Padovani, C. R. (2006). Surface electromyography of facial muscle during natural and artificial feeding of infants. Journal of Pediatrics (Rio Journal), 82(2), 103-109.
  15. Haham, A., Marom, R., Mangel, L., Botzer, E., & Dollberg, S. (2014). Prevalence of breastfeeding difficulties in newborns with a lingual frenulum: A prospective cohort series. Breastfeeding Medicine, 9(0), 1-4.
  16. Han, S. H., Kim, M. C., Choi, Y. S., Lim, J. S., & Han, K. T. (2012). A study on the genetic inheritance of ankyloglossia based on pedigree analysis. Archives of Plastic Surgery, 39(4), 329-332.
  17. Jacinto-Goncalves, S. R., Gaviao, M. B., Berzin, F., de Oliveira, A. S., & Semeguini, T. A. (2004). Electromyographic activity of perioral muscle in breastfed and non-breastfed children. The Journal of Clinical Pediatric Dentistry, 29(1). 57-62.
  18. Klockars, T., & Pitkaranta, A. (2009). Inheritance of ankyloglossia (tongue-tie). Clinical Genetics, 75(1), 98-99.
  19. Kotlow, L. (2013). Diagnosing and understanding the maxillary lip-tie (superior labial, the maxillary labial frenum) as it relates to breastfeeding. Journal of Human Lactation, 29(4). 458-464.
  20. Lundberg, J. O., Farkas-Szallasi, T., Weitzberg, E., Rinder, J., Lidholm, J., Anggaard, A., Hokfelt, T., Lundberg, J. M., & Alving, K. (1995). High nitric oxide production in human paranasal sinuses. Nature Medicine, 1(4), 370-373.
  21. McCann, S. M., Licinio, J., Wong, M. L., Yu, W. H., Karanth, S., & Rettorri, V. (1998). The nitric oxide hypothesis of aging. Experimental Gerontology, 33(7-8), 813-826.
  22. Montagu, A. (1986). Touching: The human significance of the skin. (3rd ed.). New York, NY: Harper & Row Publishers.
  23. Morris, S. E. (1978, revised 2003). A longitudinal study of feeding and pre-speech skills from birth to three years. Unpublished research study.
  24. Morris, S. E. (1985). Developmental implications for the management of feeding problems in neurologically impaired infants. Seminars in Speech and Language, 6(4), 293-315.
  25. Morris, S. E., & Klein, M. D. (2000). Pre-Feeding skills: A comprehensive resource for mealtime development. (2nd ed.). San Antonio, TX: Therapy Skill Builders.
  26. National Institutes of Health/US National Library of Medicine (NIH). (2014). Ear infection – acute. MedlinePlus Medical Encyclopedia, Updated by Neil K. Kaneshiro, MD, MHA,
  27. Northrup. C. (2005). Mother-Daughter wisdom: Creating a legacy of physical and emotional health. New York, NY: Bantam Dell.
  28. Northrup, C. (2001). The wisdom of menopause: Creating physical and emotional health and healing during the change. New York, NY: Bantam Books.
  29. Oetter, P., Richter, E. W., & Frick, S. M. (1995). M.O.R.E.: Integrating the mouth with sensory and postural functions. (2nd ed.) Hugo, MN: PDP Press.
  30. Page, D. C. (1999). The new dental-medical renaissance: Medically efficacious functional jaw orthopedics. The Functional Orthodontist: A Journal of Functional Jaw Orthopedics, 16(1), 16-25.
  31. Page, D. C. (2003a). Your jaws – your life. Baltimore, MD: SmilePage Publishing.
  32. Page, D. C. (2003b). “Real” early orthodontic treatment: From birth to age 8. The Functional Orthodontist: A Journal of Functional Jaw Orthopedics, 20 (1-2), 48-58.
  33. Schedin, U., Norman, M., Gustafsson, L. E., Herin, P., & Frostell, C. (1996). Endogenous nitric oxide in the upper airways of healthy newborn infants. Pediatric Research, 40(1), 148-151.
  34. Upledger, J. E., & Vredevoogd, J. D. (1983). Craniosacral therapy. Seattle, WA: Eastland Press.
  35. Upledger, J. E. (1996). A brain is born: Exploring the birth and development of the central nervous system. Berkley, CA: North Atlantic Book and Palm Beach Gardens, FL: The Upledger Institute.
  36. Van der Liden, F. (1986). Facial growth and facial orthopedics. Hanover Park, IL: Quintessence Publishing Co.
  37. Watkins, C. J., Leeder, S. R., & Corkhill, R. T. (1979). The relationship between breast and bottle-feeding and respiratory illness in the first year of life. Journal of Epidemiology and Community Health, 33, 180-182.


  1. Hi,
    I just came across your website today, and I had a question here although I see that this post is from a while back.
    If a baby is bottle fed what can be done to assist in proper development of the palate? What are the actual risks to palatal development from bottle feeding? Although perhaps breast feeding is ideal it is not always an option, so I would be interested in hearing your thoughts on this.

  2. Hello Tova,

    Your answers can be found in my parent-professional book Nobody Ever Told Me (or My Mother) That! Everything from Bottles and Breathing to Healthy Speech Development. I am also writing a new feeding book addressing these questions. The short answer is I have found systematic oral massage and jaw work to help reverse some of the negatives caused by bottle feeding. Additionally, keeping a child “on track” in feeding development beyond bottle feeding or breast feeding can make a big difference. I am writing books to help parents do this when possible. You are welcome to email me if you want some more specifics. Great question. di

  3. Hi,
    I do breastfeed my baby but I am concerned about her lower jaw, I know Babies jaws are set back slightly but my little girls is quite far back and she can’t seem to close her mouth, she is now five weeks old and it’s open all the time even when sleeping can you help? what is the right course of action? Thanks

  4. So I noticed when my baby was sleeping, her lower jaw was pulled back more. I overly worried wondering if this affected her breathing while sleeping and if it were normal. I worried that her jaw was messed up but after reading this I feel sooooo much better.

  5. Hello Tiffany, So sorry it took me time to get back to you. I have been out of the office. I suggest you have your baby seen by someone who has experience with these subtle problems. This could include an IBCLC and/or oral sensory-motor therapist (speech or occupational therapist) trained to work with babies who have mouth development issues. You are right – mouth breathing and a significantly retruded lower jaw are of concern. My new book “Feed Your Baby and Toddler Right” discusses these problems in detail (,204,203,200_QL40_&dpSrc=srch). If you email me, I will send you some other things to help you as well. di (

  6. Hi i am Asad,
    I noticed that My baby boy of 45 days cannot feed properly he has a tounge tie and i operated that. Now i see that he has a very less space in his mouth and o shaped throat unable to see his throat he is so irritating and uncomfortable during slèep and after feeding vomit from mouth and nose i m very worried about that kindly help me

    • Hello Asad, You are experiencing a common problem. I am hoping you were taught pre- and post- tongue revision treatment by a professional. My new book discusses other difficulties we often see in the mouth in addition to ties (e.g., missing or limited sucking pads, jaw grading problems likely related to the tongue and/or lip being tied to it, tongue cupping and grooving problems). Post release babies need to learn motor plans for feeding they could not use while they were tied. This is where an IBCLC or feeding therapist who knows this work could help you. Feeding Matters has a list of feeding therapists. The ILCA has a list of IBCLCs. My new book addresses the additional factors I am seeing. It’s the first book you see on this page: I also offer online parent education to help parents find appropriate professionals who know or are willing to learn these techniques: Please feel free to contact me if you have further questions.

  7. I am a student of speech and language pathology. Soon I will begin my clinical practice, so the information provided by this article seemed extremely important to know and interesting since many times we know the anatomy and the concepts but put them in perspective of function and how the feeding process, voice or any other area that we are working, sometimes we do not have it so clear. Thank you so much for this information. It has helped me understand many things on the subject.

    • Hello Idamyliz, Thank you for your lovely words. YOU MADE MY DAY!. My goal is to help others understand what it has taken me 40 years in practice to learn. My courses and website have further information ( I also offer a free e-course on newborn and infant mouth development if folks email me. Have a wonderful weekend. di (

  8. Hi,
    I am a student of Speech and Language Pathology and I found this article extremely important to increase my knowledge in the anatomy and physiology of babies since sometimes you must have different perspectives when explaining to parents on the subject. It is extremely important to me to also know the difference between breastfeeding and the bottle and how babies’ mouths develop in different ways when sucking. I thank you for sharing this information.

  9. Hello Angelica, Thank you for your lovely words. YOU MADE MY DAY!. My goal is to help others understand what it has taken me 40 years in practice to learn. My courses and website have further information ( I also offer a free e-course on newborn and infant mouth development if folks email me. I have a breastfeeding vs. bottle feeding comparison in my 2018 book “Feed Your Baby and Toddler Right.” They are very different processes as you said. Have a wonderful weekend. di (

  10. Good Afternoon,

    I am a graduate student in Speech-Language Pathology, and I am currently taking my dysphagia course. While looking for more research on sucking pads, I found this post. Thank you for this informative synthesis, it has helped me better conceptualize newborn development!

    • Hello Lindsey,

      Great question. Look under the Presentations section of my website You will see what you need here: Bahr, D., & Gatto, K. (2017, Nov.). Mouth and airway development, disorders, assessment, and treatment: Birth to age 7. Los Angeles, CA: ASHA Conference.

      Handout for Session 1759, References for Session 1759, ASHA Final PDF

  11. Good evening,

    My baby is six months old I see whenever she sleep she keep I u shaped tongue on the roof of the mouth.
    Should I worry about this or it’s normal.

    Pls help me I am very worried about her

  12. Hello Amy,

    Yes, we want her tongue making contact with her palate to help keep the broad palate shape. Breastfeeding also helps with this. However, if her jaw is open, you may want to do some jaw exercise at the molar areas with her. I have a free e-course explaining this. The palate (roof of the mouth) is the floor and the nasal area. Nose breathing is crucial for good health throughout life. I attached a few things for you in the email I sent you. Great question. di


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