What causes breast engorgement if it's not due to an organism causing mastitis?

Breast engorgement occurs as a result of a temporary increase in vascular and lymphatic supply to the breast tissue, particularly during the early stages of breastfeeding. When milk begins to be produced and fills the ducts, the breast tissue swells due to increased blood flow and fluid accumulation from the lymphatic system. This physiological response is normal and can happen in the early days after birth, particularly if the baby is not breastfeeding effectively or frequently enough.

Other factors, such as improper latch during feeding, dehydration, or low milk supply, can contribute to breast discomfort or issues like mastitis, but they do not inherently cause the engorgement condition itself. Engorgement is primarily about the breasts becoming overly full and swollen due to milk production and fluid dynamics rather than an infection or insufficient breastfeeding technique. Recognizing that breast engorgement is a normal transitional phase helps in managing breastfeeding effectively and understanding the body's adaptation to milk production.