If a newborn has a pit on the top of the head, it is mainly caused by the following situations: first of all, it is caused by the cranial dysplasia of the newborn, because the cranium of the newborn is often very easy to move, the bone seams are not completely closed, dysplasia can cause the condition of a pit on the top of the head, this situation is very common, plus the extrusion of the newborn by birth injuries at the time of birth, will also aggravate the newborn The pit on the top of the head. The second is caused by vitamin D deficiency rickets in newborns. If the growth of newborns is particularly rapid, coupled with the lack of vitamin D in breast milk, it can cause vitamin D deficiency rickets in newborns. This disease can cause softening of the newborn’s skull, which in turn causes the condition of pits on the top of the head.