Pierre Robin Sequence (PRS) is a rare but significant craniofacial condition that affects newborns and infants. It is defined by a triad of micrognathia (small lower jaw), glossoptosis (posterior displacement of the tongue), and airway obstruction. In many cases, it is also associated with a cleft palate. Unlike a syndrome, which involves multiple independent anomalies, PRS is classified as a “sequence” because one developmental anomaly—the underdevelopment of the mandible—triggers a cascade of related problems. 

Early recognition of PRS is vital, as it can cause life-threatening breathing difficulties, feeding problems, and impaired growth in infants. This article provides a detailed, patient-friendly overview of PRS, covering its definition, causes, risk factors, symptoms, diagnostic process, treatment, complications, and long-term outlook. 

Pierre Robin Sequence is a congenital condition present at birth. It affects essential craniofacial structures and can significantly impact a baby’s ability to breathe and feed. Parents often notice signs soon after birth, which may lead to urgent evaluation by pediatricians and specialists. Understanding what PRS is and how it differs from other craniofacial conditions is important for families and caregivers. 

The defining features include: 

• Micrognathia: an abnormally small lower jaw. 

• Glossoptosis: the tongue falling backward toward the throat. 

• Airway obstruction: breathing difficulties due to blockage by the tongue. 

Additionally, many infants with PRS also have a U-shaped cleft palate, though this is not present in every case. The developmental sequence typically begins with inadequate jaw growth in the womb. As the jaw fails to grow forward, the tongue is pushed backward and upward, which can both obstruct the airway and prevent the palate from closing properly. 

Understanding the causes of PRS helps explain why this condition develops in some babies. PRS is not a result of anything a parent did or did not do during pregnancy, but rather a complex interaction of genetic, mechanical, and neurological factors. Because the exact cause can vary between children, doctors carefully evaluate whether it is isolated or associated with another syndrome. 

The primary cause of Pierre Robin Sequence is mandibular hypoplasia (underdeveloped lower jaw) during early fetal development. This single event sets off the characteristic chain of problems. 

Contributing factors 

• Genetic: Mutations in genes affecting connective tissue, such as COL2A1, COL11A1, and COL11A2. 

• Mechanical: Intrauterine crowding or constraints, including oligohydramnios (low amniotic fluid) or twin pregnancies. 

• Neurological: Reduced fetal movement that limits jaw development. 

Risk factors 

• A family history of craniofacial anomalies. 

• Presence of syndromes such as Stickler syndrome, Treacher Collins syndrome, or 22q11.2 deletion syndrome. 

• Maternal complications during pregnancy that restrict fetal movement. 

The development of PRS follows a stepwise sequence that begins in the womb. A small jaw sets off a chain of problems that can affect the airway, palate, and overall growth. This predictable pattern explains why PRS is considered a sequence rather than a syndrome. 

PRS develops in utero and is not usually preventable. Its pathophysiology follows a cascade of events: 

1. Mandibular hypoplasia: The jaw does not grow adequately. 

2. Glossoptosis: The tongue is forced backward into the throat. 

3. Cleft palate: The tongue prevents the palate from closing, creating a U-shaped cleft. 

4. Airway obstruction: The displaced tongue narrows or blocks the airway, especially when the baby is lying on their back. 

The severity of airway obstruction depends on how underdeveloped the jaw is and whether a cleft palate is present. 

Epidemiology provides insight into how common PRS is and who may be at risk. Although rare, PRS occurs worldwide and affects families of all backgrounds. Understanding its prevalence can help guide screening and preparation for healthcare systems and families alike. 

Pierre Robin Sequence occurs in approximately 1 in 8,500 to 14,000 live births worldwide. It affects both sexes equally. About 50% of cases are isolated (non-syndromic), while the other 50% are associated with more than 40 different syndromes. Stickler syndrome is the most common syndromic association. 

Recognizing the signs and symptoms of PRS is essential for early intervention. Symptoms usually appear in the first hours or days of life and may include difficulty breathing or feeding. Parents and providers should be alert to the clinical features, as timely care can make a significant difference in outcomes. 

Airway symptoms 

• Stridor (noisy breathing) 

• Retractions during breathing 

• Cyanosis (bluish skin from lack of oxygen) 

• Apnea (pauses in breathing) 

Feeding difficulties 

• Trouble latching and sucking 

• Nasal regurgitation, especially in babies with cleft palate 

• Aspiration of milk into the lungs 

Growth issues 

• Poor weight gain or failure to thrive due to feeding challenges 

• Increased energy use from labored breathing 

Physical findings 

• Receding chin (micrognathia) 

• Visible glossoptosis 

• U-shaped cleft palate (common but not universal) 

• Ear anomalies in syndromic cases 

Diagnosing PRS involves both prenatal and postnatal evaluations. Many cases are suspected during pregnancy based on imaging studies, but confirmation usually occurs after birth. A combination of clinical evaluation, imaging, and genetic testing ensures accurate diagnosis. 

Prenatal diagnosis 

• Ultrasound: May detect micrognathia. 

• MRI: Can show glossoptosis and polyhydramnios (excess amniotic fluid due to swallowing problems). 

Postnatal diagnosis 

• Clinical evaluation: Based on the triad of features. 

• Flexible nasopharyngoscopy: To evaluate airway obstruction. 

• Sleep studies: To assess obstructive sleep apnea. 

Additional testing 

• Genetic testing for associated syndromes. 

• Eye exams to check for Stickler syndrome. 

• Hearing evaluations to detect conductive hearing loss. 

Differential diagnosis for Pierre Robin Sequence 

When evaluating a child with PRS-like symptoms, doctors must rule out other conditions. Several craniofacial syndromes and airway disorders can mimic aspects of PRS. A careful clinical workup helps ensure the correct diagnosis and treatment plan. 

Other conditions that may resemble PRS include: 

• Treacher Collins Syndrome 

• Nager Syndrome 

• Craniofacial microsomia 

• Isolated cleft palate 

• Laryngomalacia (soft laryngeal tissues causing obstruction) 

Treatment for PRS is highly individualized and depends on the severity of symptoms. Because it involves multiple aspects of a baby’s health, care is typically provided by a multidisciplinary team. Early airway stabilization and nutritional support are the main priorities in the newborn period. 

1. Airway management 

• Positioning: Prone (stomach-down) positioning helps keep the airway open. 

• Nasopharyngeal airway: A tube to bypass tongue obstruction. 

• CPAP (continuous positive airway pressure): Non-invasive ventilation for moderate obstruction. 

Surgical interventions 

• Tongue-lip adhesion (TLA): Temporarily anchors the tongue forward. 

• Mandibular distraction osteogenesis (MDO): Gradually lengthens the jaw, moving the tongue forward. 

• Tracheostomy: Used in severe, refractory cases to bypass airway obstruction. 

2. Feeding support 

• Specialized bottles designed for cleft palate. 

• Nasogastric tube for severe feeding problems. 

• Gastrostomy tube for long-term feeding support. 

3. Cleft palate repair 

• Typically performed between 9–12 months once the airway is stable. 

4. Hearing management 

• Regular hearing checks. 

• Early interventions for conductive hearing loss due to recurrent ear infections. 

Mandibular distraction osteogenesis in Pierre Robin Sequence 

Mandibular distraction osteogenesis (MDO) has become an increasingly preferred treatment for severe airway obstruction in PRS. Unlike other interventions that only manage symptoms, MDO directly addresses the underlying anatomical problem. Families often choose this option because it improves quality of life and reduces long-term complications compared to tracheostomy. 

Indications 

• Severe airway obstruction with low oxygen or elevated carbon dioxide. 

• Failure of non-surgical approaches. 

Procedure 

• Surgeons perform small cuts (osteotomies) in the jaw. 

• External devices slowly separate the bone segments over time, allowing new bone to form. 

Benefits 

• Avoids long-term tracheostomy. 

• Improves breathing and feeding. 

• Encourages normal jaw growth. 

Risks 

• Infection. 

• Facial nerve injury. 

• Complications with distraction devices. 

Without proper treatment, PRS can lead to complications that affect a child’s health and development. These may involve breathing, feeding, hearing, speech, and dental health. Recognizing potential complications early allows for timely intervention. 

Airway complications 

• Obstructive sleep apnea 

• Chronic hypoxia (low oxygen) 

Feeding and growth 

• Failure to thrive 

• Aspiration pneumonia 

Hearing 

• Conductive hearing loss from repeated ear infections 

Speech and language 

• Delays related to cleft palate and hearing loss 

Dental 

• Malocclusion (poor bite alignment) 

• Crowded teeth 

The long-term outlook for children with PRS depends on whether the condition is isolated or part of a syndrome. In many cases, early treatment leads to good outcomes. Families should understand that prognosis can vary widely, but supportive care helps most children thrive. 

• Isolated PRS: Most children achieve normal growth and development with appropriate management. 

• Syndromic PRS: Prognosis depends on the underlying syndrome, which may involve additional health challenges. 

With early diagnosis and a comprehensive treatment plan, many children with PRS go on to lead healthy, fulfilling lives. 

Most cases of PRS cannot be prevented, but certain steps can help families prepare. Prenatal diagnosis allows for early planning and safe delivery in a hospital with the necessary specialists. Families with a history of genetic conditions may also consider counseling. 

• Families with a history of syndromic PRS may benefit from genetic counseling. 

• Prenatal detection of micrognathia allows for careful delivery planning at specialized centers.

Living with PRS requires long-term care and adjustment for both the child and the family. With proper medical and social support, children with PRS can achieve their developmental milestones and enjoy a good quality of life. Parents play a vital role in coordinating care and advocating for their child’s needs. 

Practical advice 

• Work closely with a multidisciplinary team for coordinated care. 

• Use specialized feeding equipment and techniques. 

• Attend regular audiology, speech, and dental visits. 

• Connect with support groups for families managing cleft palate and craniofacial conditions. 

Long-term follow-up 

• Monitor growth and nutrition. 

• Support speech and language development. 

• Address dental and orthodontic issues as the child grows. 

Pierre Robin Sequence is a rare but serious condition that presents challenges in breathing, feeding, and growth during infancy. Prompt recognition, airway stabilization, and a multidisciplinary care plan are essential to ensure positive outcomes. Advances in surgical techniques, genetic research, and supportive therapies continue to improve the prognosis for affected children. With long-term follow-up and family support, many children with PRS can thrive and reach their full potential. 

1. Robin P. La glossoptose insuffisance de developpement du maxillaire inferieur, micrognathie, chute de la base de la langue. Bull Acad Natl Med. 1923;89:37-41. 

2. Evans KN, Sie KCY, Hopper RA, Glass RP, Hing AV. Robin sequence: from diagnosis to development of an effective management plan. Pediatrics. 2011;127(5):936-948. 

3. Breugem CC, Evans KN, Poets CF, Suri S, Picard A, Filip C, et al. Best practices for the diagnosis and evaluation of infants with Robin sequence: a clinical consensus report. JAMA Pediatr. 2016;170(9):894-902. 

4. Resnick CM, Koudstaal MJ, Breugem CC. Mandibular distraction osteogenesis in Pierre Robin Sequence: a systematic review. J Craniofac Surg. 2015;26(4):1312-1316. 

5. Denny AD, Amm CA, Schaefer RB, Lam S, Kalantarian B. Mandibular distraction osteogenesis in very young patients to avoid tracheostomy: a long-term follow-up study. Plast Reconstr Surg. 2013;131(4):1001-1010. 

6. American Cleft Palate-Craniofacial Association (ACPA). Parameters for evaluation and treatment of patients with cleft lip/palate or other craniofacial differences. Cleft Palate Craniofac J. 2018;55(1):137-156.