If you have noticed that your baby has a small indentation just above the crease of the buttocks, it is likely a sacral dimple.
In the newborn nursery, your baby’s pediatrician will look at the dimple to decide if it needs to be evaluated further. If the base of the dimple can be visualized, there is no need to worry. Most sacral dimples are harmless and will not bother your baby.
Sacral dimples that are deep, larger than 0.5cm, covered by a tuft of hair, discolored skin, or a skin tag may need to be looked at a little more closely to make sure there is not an underlying problem with the spinal cord, such as spina bifida or a tethered cord. Your doctor will likely order an ultrasound of the spine to detect any underlying abnormalities.