The Anatomy of Female Breast Explained

Written by Dr Joanna Butler from The Medical Stock Images Company

The female breast is a complex anatomical structure primarily composed of glandular tissue, fatty tissue, and connective tissues known as stroma. The proportion of these tissues varies among individuals, influencing breast size, shape, and density. The glandular component includes lobes, lobules, and ducts, which play a crucial role in lactation, while the fatty tissue provides volume and cushioning.

The breast is not directly attached to underlying muscles but is supported by fibrous bands called Cooper’s suspensory ligaments. These ligaments extend from the skin through the breast tissue to the underlying pectoral fascia, maintaining structural integrity and shape. Over time, factors such as aging, gravity, and hormonal changes may weaken these ligaments, affecting breast firmness. The breast is encased in two layers of fascia: the superficial fascia, which lies just beneath the skin, and the deep fascia, which is in close association with the pectoralis major muscle.

The Vascular Supply to the Breast

The vascular supply to the breast is primarily from the internal mammary artery and the lateral thoracic artery. These blood vessels provide essential nutrients, including oxygen, to the breast tissues. The venous drainage follows a similar pattern, with veins corresponding to the arteries returning deoxygenated blood to the heart. In addition to blood vessels, a network of nerves supplies the breast, enabling sensory perception, including sensitivity to touch, temperature, and pain.

Anatomy to Feed a Baby

Specialised structures within the breast include lobules, which contain milk-producing alveoli. These structures are particularly active during lactation when hormonal signals stimulate the alveoli to produce and secrete milk into the ductal system, eventually reaching the nipple for infant feeding. The areola, the pigmented area surrounding the nipple, contains specialised glands called Montgomery glands, which secrete an oily substance to protect and moisturise the nipple during breastfeeding.

The Lymphatic System of the Breast

The lymphatic system of the breast is essential for immune function and fluid balance. It consists of lymph nodes and lymphatic vessels that drain excess interstitial fluid and transport it back to the bloodstream. The primary lymph nodes involved in breast drainage are located in the axillary (underarm) region, along with the parasternal and supraclavicular lymph nodes. These nodes filter out harmful substances and play a key role in the immune response. Dysfunction or obstruction of the lymphatic system can lead to lymphedema, a condition characterised by fluid accumulation and swelling in the breast or nearby tissues.

The Muscular Structures

The muscular structures associated with the breast include the pectoralis major and minor, the serratus anterior, and the external oblique muscles. These muscles provide movement and structural support to the chest wall, indirectly influencing breast positioning. While the breast itself lacks muscle tissue, regular exercise targeting these muscles can improve chest tone and support.

Conclusion

Understanding the anatomy of the breast is crucial for recognising normal physiological changes, detecting abnormalities, and promoting overall breast health. Medical illustrations of breast anatomy can be used during doctor to patient communications, within health education and to improve understanding. By including diverse ethnicities in our medical illustrations, we aim to create a more inclusive and effective healthcare system that serves everyone. Such efforts not only improve education and patient care but also contribute to a more just and empathetic society.