Clinically there is no sleep regression period, Min Jiang will baby sleep pattern change, poor sleep quality, poor condition and other performance called sleep regression period. 1. Changes in sleep pattern: babies may have changes in sleep pattern, may appear to sleep during the day and play at night, the reversal of day and night state, sleep during the day, time, single sleep time will also be relatively shortened. 2. Poor sleep quality: some babies may also have symptoms of frequent rolling over and waking up easily, which will make the baby’s sleep quality worse. 3. Poor state: As the quality of baby’s sleep deteriorates, the duration of sleep is shortened, which will lead to poor mental state caused by poor sleep. If the baby’s sleep quality is not good for a long time, it is recommended to go to the child health department of the hospital in time, under the guidance of the doctor to be targeted treatment.