Characteristics of a balanced supply and demand during lactation include adequate milk supply, normal bowel movements, long sucking time and long sleeping time. 1. Adequate milk supply: Balanced supply and demand during lactation means that the amount of milk produced by the mother’s breast is just enough to satisfy the child’s demand and the mother will be bloated with milk and there will be overflow of milk, which means that there is an adequate supply of milk. 2. Normal urination and defecation: with a balanced supply and demand during breastfeeding, the blood volume in the baby’s body is in a normal state, and filtered through the kidneys, the baby urinates more than 6 times a day and defecates about 1~2 times a day. 3. Long sucking time: supply and demand are balanced during lactation, mother’s milk is relatively abundant, and the baby sucks milk for about 15 minutes and has swallowing sound. 4. Long sleeping time: with a balanced supply and demand during the breastfeeding period, the baby sleeps for a longer time and will not cry and disturb due to hunger, which will affect the quality of sleep. Breastfeeding usually reaches the balance of supply and demand in about 42 days, and the body gradually recovers, and the nutrition will gradually reach the level of balance of supply and demand.