My Baby's Soft Spot Is Still Open
Medically reviewed by Dr. Sarah Chen, MD, FAAP · Board-Certified Pediatrician
Content reviewed against published AAP, NIH, CDC guidelines
Last reviewed:
Your baby's physical development is unique, and concerns about soft spot is still open, here is what you need to know.
The short answer
The anterior fontanelle normally closes between 9 and 18 months, but some healthy babies' fontanelles remain open until 24 months. A fontanelle that is still open beyond 18 months should be evaluated, as it can sometimes indicate conditions like rickets, hypothyroidism, or other causes. However, many late-closing fontanelles are simply a normal variant.
Key takeaways
- The anterior fontanelle normally closes between 9 and 18 months, but some healthy babies' fontanelles remain open until 24 months. A fontanelle that is still open beyond 18 months should be evaluated, as it can sometimes indicate conditions like rickets, hypothyroidism, or other causes. However, many late-closing fontanelles are simply a normal variant.
- Usually normal when: The fontanelle is getting progressively smaller.
- Call your doctor if: Bulging fontanelle with vomiting, fever, or lethargy.
- Varies by age — see the age-by-age breakdown below
“Supervised tummy time is recommended daily from the time the baby comes home from the hospital to help prevent flat head syndrome and to strengthen neck and shoulder muscles.”
Parents everywhere have the same worry. You are doing the right thing by looking into it.
What Parents Should Know
According to AAP, NIH, CDC guidelines, the anterior fontanelle normally closes between 9 and 18 months, but some healthy babies' fontanelles remain open until 24 months. A fontanelle that is still open beyond 18 months should be evaluated, as it can sometimes indicate conditions like rickets, hypothyroidism, or other causes. However, many late-closing fontanelles are simply a normal variant. At 9-12 months, some fontanelles are beginning to close, but many are still open. This is within normal range. Your pediatrician will check the fontanelle at every visit and is monitoring for normal closure. It is generally considered normal when the fontanelle is getting progressively smaller. However, you should contact your pediatrician promptly if bulging fontanelle with vomiting, fever, or lethargy.
Normal vs. Concerning
By Age
What to expect by age
9-12 months
Some fontanelles are beginning to close, but many are still open. This is within normal range. Your pediatrician will check the fontanelle at every visit and is monitoring for normal closure.
12-15 months
The fontanelle may be getting smaller or may still be clearly open. Both are within the normal range. Your pediatrician will check if it is getting smaller over time.
15-18 months
If the fontanelle is still open, your pediatrician may monitor more closely. It may still close normally, but if it is large, blood tests to check vitamin D levels, thyroid function, and calcium may be ordered.
18-24 months
An open fontanelle at this age warrants evaluation. Common treatable causes include vitamin D deficiency/rickets and hypothyroidism. If your child is otherwise developing normally, the cause is often easily correctable.
What to Tell Your Pediatrician
- Describe when you first noticed soft spot is still open and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if the fontanelle is still open after 18 months.
- Mention if the fontanelle seems to be getting larger.
- 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
- The fontanelle is getting progressively smaller.
- Your baby is developing normally.
- Head growth is normal.
- Your baby is under 18 months.
- The fontanelle is still open after 18 months.
- The fontanelle seems to be getting larger.
- The fontanelle is bulging or tense.
- Bulging fontanelle with vomiting, fever, or lethargy.
- Fontanelle with signs of increased intracranial pressure.
What You Can Do at Home
- Keep track of when you notice soft spot is still open — noting the time of day, duration, and any triggers can help your pediatrician.
- Remember that the fontanelle is getting progressively smaller — this is generally within the range of normal.
- At 9-12 months, focus on observation rather than intervention unless your pediatrician advises otherwise.
- Provide plenty of supervised floor time and tummy time to support your baby's physical development.
- While monitoring at home, seek immediate care if bulging fontanelle with vomiting, fever, or lethargy.
Related Conditions
My Baby's Soft Spot Is Closing Early
The anterior fontanelle (soft spot) typically closes between 9 and 18 months, though some babies' fontanelles close as early as 3 months without any problem. Early closure is only concerning if it restricts brain growth (craniosynostosis). Your pediatrician monitors head growth and fontanelle size at every visit.
My Baby's Head Is Growing Too Fast
Head circumference is monitored at every well visit because it reflects brain growth. Crossing upward percentile lines in head growth can indicate benign familial macrocephaly (runs in families) or, rarely, increased intracranial pressure. Your pediatrician will evaluate the pattern, fontanelle, and development to determine if further investigation is needed.
Related Resources
Milestone Checklists by Age
Track your baby's developmental milestones from birth to 5 years with age-specific checklists.
Month-by-Month Development
Detailed monthly development guides from birth through 24 months.
When to Call the Doctor
General guide on when to call the pediatrician, visit urgent care, or go to the ER.
Frequently asked questions
Is soft spot is still open normal?
When should I call the doctor about soft spot is still open?
When is soft spot is still open normal?
What causes soft spot is still open?
What should I mention to my pediatrician about soft spot is still open?
Is soft spot is still open normal at 9-12 months?
Is soft spot is still open normal at 12-15 months?
Should I go to the ER for soft spot is still open?
Does soft spot is still open go away on its own?
References
Doctor Visit Checklist
Bring this checklist to your next pediatrician visit to discuss My Baby's Soft Spot Is Still Open.
Things to mention
- Describe when you first noticed soft spot is still open and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if the fontanelle is still open after 18 months.
- Mention if the fontanelle seems to be getting larger.
- 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
- The fontanelle is still open after 18 months.
- The fontanelle seems to be getting larger.
- The fontanelle is bulging or tense.
Urgent signs to report immediately
- Bulging fontanelle with vomiting, fever, or lethargy.
- Fontanelle with signs of increased intracranial pressure.
My notes
From ismybabyalright.com — free, evidence-based baby health guides
All content follows our editorial policy and is reviewed against published clinical guidelines.
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Related Resources
Bottom line
Most cases of soft spot is still open are normal. Talk to your pediatrician if bulging fontanelle with vomiting, fever, or lethargy.
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 Physical Concerns
My Baby's Soft Spot Is Closing Early
The anterior fontanelle (soft spot) typically closes between 9 and 18 months, though some babies' fontanelles close as early as 3 months without any problem. Early closure is only concerning if it restricts brain growth (craniosynostosis). Your pediatrician monitors head growth and fontanelle size at every visit.
My Baby's Head Is Growing Too Fast
Head circumference is monitored at every well visit because it reflects brain growth. Crossing upward percentile lines in head growth can indicate benign familial macrocephaly (runs in families) or, rarely, increased intracranial pressure. Your pediatrician will evaluate the pattern, fontanelle, and development to determine if further investigation is needed.
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Yes — for premature babies, developmental milestones should be assessed using adjusted (corrected) age, not chronological age, until at least 2 years of age. Adjusted age is calculated by subtracting the number of weeks your baby was born early from their actual age. For example, a 6-month-old born 2 months early would have an adjusted age of 4 months, and should be assessed against 4-month milestones. Most pediatricians use adjusted age for developmental assessment through age 2-3, and for growth charts through age 2.
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