My Baby Has a Dimple at the Base of Their Spine
Medically reviewed by Dr. Michael Okonkwo, MD, FAAP · Board-Certified Neonatologist
Content reviewed against published AAP, AAP, AAP guidelines
Last reviewed:
If your baby has been diagnosed with or you suspect has a dimple at the base of their spine, here is what the evidence says.
The short answer
A sacral dimple is a small indentation at the base of the spine, just above the buttocks. Most are simple, shallow dimples that are completely normal and never cause problems. Your pediatrician will check the dimple at well visits. Occasionally, if it's deep, large, or has unusual features, an ultrasound may be ordered to ensure the spine is developing normally.
Key takeaways
- A sacral dimple is a small indentation at the base of the spine, just above the buttocks. Most are simple, shallow dimples that are completely normal and never cause problems. Your pediatrician will check the dimple at well visits. Occasionally, if it's deep, large, or has unusual features, an ultrasound may be ordered to ensure the spine is developing normally.
- Usually normal when: Your baby has a small, shallow dimple within the buttock crease
- Call your doctor if: The dimple is draining fluid, pus, or has signs of infection (redness, swelling, warmth)
- Varies by age — see the age-by-age breakdown below
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What Parents Should Know
According to AAP guidelines, a sacral dimple is a small indentation at the base of the spine, just above the buttocks. Most are simple, shallow dimples that are completely normal and never cause problems. Your pediatrician will check the dimple at well visits. Occasionally, if it's deep, large, or has unusual features, an ultrasound may be ordered to ensure the spine is developing normally. At 0-3 months, sacral dimples are usually noticed at birth or during early checkups. Your pediatrician will assess the dimple's size, depth, and location. Most are "simple" dimples: small, shallow, located within the buttock crease, with normal-looking skin. These rarely need further testing. If the dimple is large, deep, located higher on the back, or has hair, skin tag, or unusual coloring, your doctor may order a spinal ultrasound to check for underlying spinal cord issues. It is generally considered normal when your baby has a small, shallow dimple within the buttock crease. However, you should contact your pediatrician promptly if the dimple is draining fluid, pus, or has signs of infection (redness, swelling, warmth).
Normal vs. Concerning
When to Seek Immediate Care
- The dimple is draining fluid, pus, or has signs of infection (redness, swelling, warmth)
- Your baby develops weakness in the legs, asymmetric movement, or difficulty moving lower limbs
- The dimple has a tuft of hair, skin tag, or unusual discoloration that wasn't previously evaluated
- Your baby has bowel or bladder control issues as they grow older (may indicate tethered cord)
By Age
What to expect by age
0-3 months
Sacral dimples are usually noticed at birth or during early checkups. Your pediatrician will assess the dimple's size, depth, and location. Most are "simple" dimples: small, shallow, located within the buttock crease, with normal-looking skin. These rarely need further testing. If the dimple is large, deep, located higher on the back, or has hair, skin tag, or unusual coloring, your doctor may order a spinal ultrasound to check for underlying spinal cord issues.
3-6 months
If your baby's sacral dimple was noted as simple at birth, no further monitoring is typically needed. If an ultrasound was recommended and shows normal spine anatomy, you can be reassured. Occasionally, findings on ultrasound require follow-up with a pediatric neurosurgeon, but most sacral dimples are benign and never cause symptoms.
6-12 months
By this age, if your baby's sacral dimple has never shown concerning features and your baby is developing normally, it's simply a normal variation. Watch for any signs of spinal cord issues as your baby grows: asymmetric leg movement, weakness, or unusual gait when learning to walk. These are very rare, but mention them if noticed.
12 months+
Most children with simple sacral dimples have no issues throughout childhood. If your child was found to have a spinal abnormality on ultrasound or imaging, they may need ongoing monitoring by a pediatric neurosurgeon. Otherwise, the sacral dimple is just a harmless variation - no different than any other birthmark or skin variation.
What to Tell Your Pediatrician
- Describe when you first noticed has a dimple at the base of their spine and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if you've noticed a dimple on your baby's lower back and want it checked.
- Mention if the dimple seems deeper than you remember or has changed appearance.
- 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 has a small, shallow dimple within the buttock crease
- The skin around and in the dimple looks completely normal
- Your pediatrician examined the dimple and noted it as a "simple" or "benign" sacral dimple
- Your baby is moving both legs equally and developing normally
- An ultrasound was done (if ordered) and showed normal spine anatomy
- You've noticed a dimple on your baby's lower back and want it checked
- The dimple seems deeper than you remember or has changed appearance
- You're unsure whether the dimple is within normal range
- Your baby has other birthmarks or skin variations near the dimple
- The dimple is draining fluid, pus, or has signs of infection (redness, swelling, warmth)
- Your baby develops weakness in the legs, asymmetric movement, or difficulty moving lower limbs
- The dimple has a tuft of hair, skin tag, or unusual discoloration that wasn't previously evaluated
- Your baby has bowel or bladder control issues as they grow older (may indicate tethered cord)
What You Can Do at Home
- Keep track of when you notice has a dimple at the base of their spine — noting the time of day, duration, and any triggers can help your pediatrician.
- Remember that your baby has a small, shallow dimple within the buttock crease — 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 the dimple is draining fluid, pus, or has signs of infection (redness, swelling, warmth).
Related Resources
Frequently asked questions
Is has a dimple at the base of their spine normal?
When should I call the doctor about has a dimple at the base of their spine?
When is has a dimple at the base of their spine normal?
What causes has a dimple at the base of their spine?
What should I mention to my pediatrician about has a dimple at the base of their spine?
Is has a dimple at the base of their spine normal at 0-3 months?
Is has a dimple at the base of their spine normal at 3-6 months?
Should I go to the ER for has a dimple at the base of their spine?
Does has a dimple at the base of their spine go away on its own?
References
Doctor Visit Checklist
Bring this checklist to your next pediatrician visit to discuss My Baby Has a Dimple at the Base of Their Spine.
Things to mention
- Describe when you first noticed has a dimple at the base of their spine and how it has changed over time.
- Note your baby's current age and which age-specific patterns you are seeing.
- Mention if you've noticed a dimple on your baby's lower back and want it checked.
- Mention if the dimple seems deeper than you remember or has changed appearance.
- Bring a list of any questions or observations you want to discuss at the appointment.
Observations to share
- You've noticed a dimple on your baby's lower back and want it checked
- The dimple seems deeper than you remember or has changed appearance
- You're unsure whether the dimple is within normal range
Urgent signs to report immediately
- The dimple is draining fluid, pus, or has signs of infection (redness, swelling, warmth)
- Your baby develops weakness in the legs, asymmetric movement, or difficulty moving lower limbs
- The dimple has a tuft of hair, skin tag, or unusual discoloration that wasn't previously evaluated
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 has a dimple at the base of their spine are normal. Talk to your pediatrician if the dimple is draining fluid, pus, or has signs of infection (redness, swelling, warmth).
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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