Colostrum
Colostrum is a special milk for the baby's early feedings. It is made by the milk glands starting early in pregnancy. It is thicker than other milk and just what your baby needs for the first few days. It is rich in protein, antibodies, vitamins and minerals. Colostrum is the perfect first food for your baby.
During the first 3-4 days your breasts will begin to feel fuller before feedings. The milk glands are changing from making colostrum to making milk. People say the milk is "coming in." The breasts are making MORE milk, because your baby is ready for more.
As the milk comes in, your breasts may become engorged (swollen). Most mothers feel heavier or fuller before feedings but do not get engorged. Breastfeeding at least every 2 - 3 hours during the day and at least once at night will help keep your breasts comfortable as your milk comes in.
When your baby is older (between 2-12 weeks), your breasts may become a little softer and smaller. This does NOT mean you have less milk. Your breasts are getting used to holding milk and are less swollen.
Let-down
As your baby starts to nurse, your milk starts to flow. Several times during a feeding your milk glands release more milk. This is called let-down (or milk ejection reflex). The same hormone that causes the let-down makes your uterus contract (tighten). As your milk lets down, you may also feel your uterus cramp and have heavier vaginal bleeding. After the first few days, the uterus is smaller and you do not feel that cramping anymore. Some mothers feel a tingling or tightening in their breasts with the let-down at the start of each feeding. Some mothers do not feel the let-down but see their babies start to gulp as the milk comes faster.
Making enough milk
When you nurse as long and as often as your baby wants, you are telling your breasts how much milk to make. This is often called supply meets demand. Supply meets demand as long as you breastfeed, even when your baby is bigger. Your body makes as much milk as your baby is taking.
Source: Nutrition NC
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