The baby only takes one side of the milk can be considered from the following two aspects: first, the baby’s own reasons; second, the mother’s reasons. The first one is the baby’s reason, such as the common clinical flat head deformity or oblique neck, which causes the baby’s head to be habitually biased to one side, for example, if the right side has oblique neck, his head will be habitually biased to the right side, and the mother is accustomed to holding the baby in one direction, so the phenomenon of only one side of milk will appear. In this case, it is recommended that the mother can change the position, for example, from the left side to the right side, which can improve the situation. Secondly, the mother’s own reasons, such as blocked mammary glands or insufficient milk, will cause the baby to struggle to eat the milk, so he will give up this side and simply prefer to eat the other side. For this situation, it is still advisable to let the baby suck more milk or to perform breast health massage, which can be improved.