Cri du Chat Syndrome (5p Deletion) in Babies
Medically reviewed by Dr. Michael Okonkwo, MD, FAAP · Board-Certified Neonatologist
Content reviewed against published NIH, NIH guidelines
Last reviewed:
If your baby has been diagnosed with or you suspect cri du chat syndrome (5p deletion) in babies, here is what the evidence says.
The short answer
Cri du chat syndrome (also called 5p minus or 5p deletion syndrome) is a rare chromosomal condition affecting about 1 in 15,000 to 50,000 newborns, caused by a deletion on the short arm of chromosome 5. It is named for the characteristic high-pitched, cat-like cry heard in affected infants, which is caused by problems with the larynx and nervous system. Children have intellectual disability, delayed development, small head size (microcephaly), and distinctive facial features. With early intervention and supportive therapies, children can make significant developmental progress.
Key takeaways
- Cri du chat syndrome (also called 5p minus or 5p deletion syndrome) is a rare chromosomal condition affecting about 1 in 15,000 to 50,000 newborns, caused by a deletion on the short arm of chromosome 5. It is named for the characteristic high-pitched, cat-like cry heard in affected infants, which is caused by problems with the larynx and nervous system. Children have intellectual disability, delayed development, small head size (microcephaly), and distinctive facial features. With early intervention and supportive therapies, children can make significant developmental progress.
- Usually normal when: Your baby with cri du chat syndrome is making steady, gradual developmental progress with early intervention
- Call your doctor if: Your baby has difficulty breathing, turns blue, or shows signs of a heart problem — seek emergency care
- Varies by age — see the age-by-age breakdown below
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What Parents Should Know
According to NIH guidelines, cri du chat syndrome (also called 5p minus or 5p deletion syndrome) is a rare chromosomal condition affecting about 1 in 15,000 to 50,000 newborns, caused by a deletion on the short arm of chromosome 5. It is named for the characteristic high-pitched, cat-like cry heard in affected infants, which is caused by problems with the larynx and nervous system. Children have intellectual disability, delayed development, small head size (microcephaly), and distinctive facial features. With early intervention and supportive therapies, children can make significant developmental progress. At 0-3 months, the hallmark feature of cri du chat syndrome is a high-pitched, mewing cry in the newborn period that sounds similar to a cat. This cry is caused by structural differences in the larynx and is often what leads to diagnosis. Other features present at birth may include low birth weight, microcephaly (small head), a round face, widely spaced eyes, low-set ears, a small jaw, and low muscle tone (hypotonia). Feeding difficulties are common due to poor suck and swallow coordination. Diagnosis is confirmed with chromosomal microarray or karyotype showing a 5p deletion. It is generally considered normal when your baby with cri du chat syndrome is making steady, gradual developmental progress with early intervention. However, you should contact your pediatrician promptly if your baby has difficulty breathing, turns blue, or shows signs of a heart problem — seek emergency care.
Normal vs. Concerning
By Age
What to expect by age
0-3 months
The hallmark feature of cri du chat syndrome is a high-pitched, mewing cry in the newborn period that sounds similar to a cat. This cry is caused by structural differences in the larynx and is often what leads to diagnosis. Other features present at birth may include low birth weight, microcephaly (small head), a round face, widely spaced eyes, low-set ears, a small jaw, and low muscle tone (hypotonia). Feeding difficulties are common due to poor suck and swallow coordination. Diagnosis is confirmed with chromosomal microarray or karyotype showing a 5p deletion.
1-6 months
The characteristic high-pitched cry typically becomes less distinctive over time as the larynx grows. Feeding difficulties often persist, and some babies may require specialized nipples or feeding therapy. Hypotonia affects motor development, and head control is often delayed. Early intervention services including physical, occupational, and speech therapy should begin as early as possible. Some babies may have heart defects that require monitoring or treatment.
6-12 months
Motor development is significantly delayed — sitting independently is often achieved later than typical. Babies may be socially engaged and responsive, though communication development is notably delayed. The characteristic facial features may become more or less apparent as the child grows. Cardiac evaluation, hearing testing, and vision assessment should be completed. Some children develop recurrent respiratory infections due to immune system differences.
1-3 years
Children with cri du chat syndrome continue to make developmental progress at their own pace. Walking may be achieved between 2-6 years. Speech and language are typically the most significantly affected areas, and many children benefit from augmentative and alternative communication (AAC) systems, sign language, or picture communication boards. Behavioral challenges such as hyperactivity, aggression, or self-stimulatory behaviors may emerge. Intellectual disability ranges from moderate to severe but some children have milder involvement.
What to Tell Your Pediatrician
- Describe when you first noticed cri du chat syndrome (5p deletion) in babies and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if your newborn has an unusually high-pitched cry and you notice facial features such as a round face, small head, or widely spaced eyes.
- Mention if your baby with cri du chat syndrome has persistent feeding difficulties and poor weight gain.
- Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
- Bring a list of any questions or observations you want to discuss at the appointment.
What Should You Do?
When to take action
- Your baby with cri du chat syndrome is making steady, gradual developmental progress with early intervention
- Your baby is socially engaged, interactive, and responsive to caregivers
- Your baby is communicating through gestures, signs, or AAC even without spoken words
- Your baby's heart defects (if any) are stable and being monitored
- Your newborn has an unusually high-pitched cry and you notice facial features such as a round face, small head, or widely spaced eyes
- Your baby with cri du chat syndrome has persistent feeding difficulties and poor weight gain
- Your child is not making developmental progress despite early intervention services
- Your baby has difficulty breathing, turns blue, or shows signs of a heart problem — seek emergency care
- Your baby is unable to feed and is becoming dehydrated — this requires urgent medical attention
What You Can Do at Home
- Keep track of when you notice cri du chat syndrome (5p deletion) in babies — noting the time of day, duration, and any triggers can help your pediatrician.
- Remember that your baby with cri du chat syndrome is making steady, gradual developmental progress with early intervention — this is generally within the range of normal.
- At 0-3 months, focus on observation rather than intervention unless your pediatrician advises otherwise.
- Follow any care instructions from your pediatrician. Keep a written log of symptoms to bring to appointments.
- While monitoring at home, seek immediate care if your baby has difficulty breathing, turns blue, or shows signs of a heart problem — seek emergency care.
Related Conditions
My Baby's Head Seems Too Small (Microcephaly)
A baby's head circumference is measured at every well-child visit to track brain growth. A head that is smaller than expected does not always mean there is a problem - genetics play a major role, and some families naturally have smaller head sizes. However, if the head circumference is significantly below normal or is falling off its growth curve, your pediatrician will want to investigate further.
Baby High-Pitched Screaming
A high-pitched scream can have many causes, ranging from completely normal (excitement, frustration, experimentation with voice) to potentially concerning (pain, illness, or neurological issues). Many babies go through a "screaming phase" around 4-8 months when they discover they can make loud, high-pitched sounds - this is a normal vocal development milestone. However, a sudden, persistent, inconsolable high-pitched cry that is different from your baby's usual cry, especially when accompanied by other symptoms, should be evaluated by a doctor.
Related Resources
Frequently asked questions
Is cri du chat syndrome (5p deletion) in babies normal?
When should I call the doctor about cri du chat syndrome (5p deletion) in babies?
When is cri du chat syndrome (5p deletion) in babies normal?
What causes cri du chat syndrome (5p deletion) in babies?
What should I mention to my pediatrician about cri du chat syndrome (5p deletion) in babies?
Is cri du chat syndrome (5p deletion) in babies normal at 0-3 months?
Is cri du chat syndrome (5p deletion) in babies normal at 1-6 months?
Should I go to the ER for cri du chat syndrome (5p deletion) in babies?
Does cri du chat syndrome (5p deletion) in babies go away on its own?
References
Doctor Visit Checklist
Bring this checklist to your next pediatrician visit to discuss Cri du Chat Syndrome (5p Deletion) in Babies.
Things to mention
- Describe when you first noticed cri du chat syndrome (5p deletion) in babies and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if your newborn has an unusually high-pitched cry and you notice facial features such as a round face, small head, or widely spaced eyes.
- Mention if your baby with cri du chat syndrome has persistent feeding difficulties and poor weight gain.
- Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
- Bring a list of any questions or observations you want to discuss at the appointment.
Observations to share
- Your newborn has an unusually high-pitched cry and you notice facial features such as a round face, small head, or widely spaced eyes
- Your baby with cri du chat syndrome has persistent feeding difficulties and poor weight gain
- Your child is not making developmental progress despite early intervention services
Urgent signs to report immediately
- Your baby has difficulty breathing, turns blue, or shows signs of a heart problem — seek emergency care
- Your baby is unable to feed and is becoming dehydrated — this requires urgent medical attention
My notes
From ismybabyalright.com — free, evidence-based baby health guides
All content follows our editorial policy and is reviewed against published clinical guidelines.
2,705 evidence-based guides6 authoritative medical sources5 medical advisory board members
Related Resources
Bottom line
Most cases of cri du chat syndrome (5p deletion) in babies are normal. Talk to your pediatrician if your baby has difficulty breathing, turns blue, or shows signs of a heart problem — seek emergency care.
Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.
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Related Medical Concerns
My Baby's Head Seems Too Small (Microcephaly)
A baby's head circumference is measured at every well-child visit to track brain growth. A head that is smaller than expected does not always mean there is a problem - genetics play a major role, and some families naturally have smaller head sizes. However, if the head circumference is significantly below normal or is falling off its growth curve, your pediatrician will want to investigate further.
Baby High-Pitched Screaming
A high-pitched scream can have many causes, ranging from completely normal (excitement, frustration, experimentation with voice) to potentially concerning (pain, illness, or neurological issues). Many babies go through a "screaming phase" around 4-8 months when they discover they can make loud, high-pitched sounds - this is a normal vocal development milestone. However, a sudden, persistent, inconsolable high-pitched cry that is different from your baby's usual cry, especially when accompanied by other symptoms, should be evaluated by a doctor.
My Baby's Head Shape Looks Abnormal
Many babies develop temporary head shape irregularities that are completely normal. A cone-shaped head from vaginal delivery reshapes within days. Mild positional flattening (plagiocephaly) from sleeping on the back is very common and usually improves with repositioning and tummy time. However, head shape changes involving ridges, a persistently bulging fontanelle, or rapid head growth changes should be evaluated to rule out craniosynostosis.
Achondroplasia (Dwarfism) in Babies
Achondroplasia is the most common form of short-limbed dwarfism, affecting about 1 in 15,000 to 40,000 births. It is caused by a mutation in the FGFR3 gene and is usually apparent at birth with characteristic features including short limbs, a larger head, and a prominent forehead. Intelligence is normal. With monitoring for specific complications and supportive care, children with achondroplasia lead full, active, and independent lives.
Adenoid Hypertrophy and Breathing
Adenoids are lymphoid tissue located behind the nose that help fight infection in young children. When adenoids become enlarged (adenoid hypertrophy), they can block the nasal airway, causing chronic mouth breathing, snoring, nasal speech, and sleep-disordered breathing. Enlarged adenoids are most common between ages 2-7 and are a leading cause of obstructive sleep apnea in young children. Treatment ranges from watchful waiting and nasal steroids to surgical removal (adenoidectomy) if breathing or sleep is significantly affected.
Adrenoleukodystrophy (ALD) in Babies
X-linked adrenoleukodystrophy (X-ALD) is a genetic disorder affecting about 1 in 17,000 newborns, caused by mutations in the ABCD1 gene on the X chromosome. It primarily affects boys and impairs the breakdown of very long-chain fatty acids (VLCFAs), which accumulate and damage the myelin sheath in the brain and the adrenal glands. The most severe form, cerebral ALD, typically affects boys between ages 4-10 with rapid neurological decline. Newborn screening now enables early detection, and hematopoietic stem cell transplant or gene therapy performed before significant brain involvement can be life-saving.