Milk production during pregnancy generally begins around the midpoint of pregnancy, between weeks 16 and 22. At this stage, the body starts producing colostrum, which is a thick, yellowish milk rich in nutrients and antibodies. This colostrum serves as the baby's first food after birth. Some pregnant women may even notice faint yellow or orange stains on their bras due to colostrum leaking, although not all women experience leaking. This early milk production happens internally in the breasts and prepares the body for feeding after delivery. After birth, the breast milk production progresses through three stages:
- Colostrum (present from mid-pregnancy and shortly after birth)
- Transitional milk (usually comes in around 3-5 days after birth)
- Mature breast milk (typically comes in around 1-2 weeks postpartum)
Mature breast milk is the final form and provides the baby with the necessary nutrition for growth and development. So, milk (in the form of colostrum) "comes in" during pregnancy starting at about 16 to 22 weeks, but the significant milk production you might feel and see usually happens after the baby is born.
