How will my breasts change as my baby grows?
As babies grow, the breasts change in appearance and fullness. They may feel lumpy, warm, full, hard, or soft, depending on the number of days since birth or the amount of time since the baby’s last feed. A decrease in milk supply is unlikely as long as the baby is growing well and breastfeeding normally. After 5 months of breastfeeding, the breasts will rarely feel full and by 15 months of breastfeeding they will be back to their pre-pregnancy size.
Here is a rough guide to the normal changes mothers can expect in their breasts:
- Days 1 to 2: The breasts have lumpy areas, similar to the consistency of oatmeal. They are very warm but do not feel full.
- Days 2 to 4: The milk comes in and the breasts feel tender, heavy, and full. If breastfeeding is not going well, they may be very full or even hard.
- Days 5 to 30: The breasts feel very full before the baby feeds and softer afterwards. They are very full by the time the baby wakes from a longer sleep.
- Months 1 to 5: The breasts feel fuller before feeds and only feel very full when the baby wakes from a longer sleep. They are especially soft in the evenings during the evening fussies.
- After Month 5: The breasts rarely feel full. When they do, it is usually in the morning after a longer sleep.
- By 15 months, the breasts are back to their pre-pregnancy size (Kent 1999).
Mothers with a large milk supply tend to notice more breast fullness. Those with larger breasts notice fewer changes.
Breasts change in appearance and fullness as the baby grows. Sometimes these changes are mistaken as a sign that a mother is “losing her milk”.
A decrease in milk supply is rare without a cause. Worrying about your milk supply is like worrying that your leg will stop working; it can happen but there is usually a cause. A decrease in milk supply is unlikely to happen as long as your baby is growing well and you are:
Mothers may not notice much filling if:
Kent JC, Mitoulas L, Cox DB, et al. Breast volume and milk production during extended lactation in women. Exp Physiol. 1999 Mar;84(2):435-47