The normal breast

Authors: Mia Demant, MD, Magnus Balslev Avnstorp, MD and Mia Steffenssen, MD

The breast consists of a milk-producing mammary gland (green), enclosed by a skin envelope (yellow), resting on its breast footprint (blue). The footprint rests on the pectoral muscles and anterior thoracic wall. The mammary gland consists of adipose tissue (fat), milk-producing lobules and milk ducts leading the milk to the nipple-areola complex (NAC).

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The normal breast is tear-shaped and the dimensions and weight of the breast vary widely among women. The NAC point forward and a little laterally. In most women, one breast is slightly larger than the other, and more obvious persistent asymmetry is seen in up to 25% of all women (1).

Standard anthropometric breast measurement

The standard measures of a young woman with medium-sized breasts (300-500 ml) are:

• Jugulum (J) – nipple (N) distance: 19-21 cm
• Medio clavicular point (MCP) – nipple distance: 19-21 cm
• Nipple – inframammary fold (IMF) distance: 5-6 cm
• Nipple – sternal bone (S) distance: 9-11 cm

Acknowledgments

Illustrators: Caroline Lilja, med.stud., Christian Paaskesen, med.stud.