Female breasts contain different types of fibrous, fatty and glandular tissue:

  • fibrous, or connective or supportive tissue is the same tissue that ligaments and scar tissue are made of. 
  • fatty tissue fills in the spaces between fibrous and glandular tissue and largely determines your breast size 
  • glandular tissue includes the breast lobes and breast ducts

Non-fatty tissue is referred to as fibroglandular tissue. There are also bands of flexible, supportive, connective tissue called ligaments, which stretch from the skin to the chest wall to hold the breast tissue in place. Muscle plays an important role too. The pectoral muscle lies against the chest wall underneath both breasts, giving them support. Blood vessels provide oxygen to the breast tissue and carry away waste.