Three months baby sleep head swaying left and right may be a normal phenomenon, but may also be vitamin D deficiency rickets and other diseases, need to choose the treatment according to the specific cause. 1. Normal phenomenon: three-month-old baby brain is in the stage of rapid development, brain neuron growth baby may appear dreaming, will show the symptoms of head swaying during sleep, is a normal phenomenon, parents can pat the baby to relieve. 2. Vitamin D deficiency rickets: mainly due to the lack of vitamin D baby sweat more stimulation of the scalp and shaking the head and other nervous system excitability increased performance, at this time you can follow the doctor’s orders to supplement vitamin D and calcium, daily life need to be appropriate sun exposure, promote skin vitamin D synthesis. If necessary, supplement other minerals and vitamins. All of the above drugs should be used under the guidance of a doctor, avoid self-medication. If your baby is swaying from side to side in sleep, it is recommended to consult a doctor for evaluation and management by a specialist.