The primary function of breasts is to produce milk following the birth of a baby (lactation). Each breast is made up of 15-20 lobes. These contain the milk-producing glands and ducts along which the milk travels to the nipple. Fat and fibrous tissue surround these structures and give the breasts their individual size and shape. The breasts also contain blood vessels, lymph glands and nerves. It is normal for one breast to be slightly larger than the other. The size of the breast does not determine how much milk it will produce.
Normal breast changes during life
From adolescence to menopause, breast tissue is affected by the hormonal changes associated with the menstrual cycle, pregnancy and lactation. Breast tissue can become more tender and lumpy just prior to a menstrual period, and less tender and lumpy after a period.
It is normal and quite common for breasts to be lumpy or have benign (non-cancerous) nodules.
During the perimenopausal years, when women transition from regular periods to their final period (menopause), women often experience increased breast discomfort because of a change in hormone levels that affects breast tissue.
After menopause, the glandular tissue of the breast is largely replaced by fatty tissue.
When to see your doctor
It is important to know your own breasts so you can tell if any changes occur.
You should see your doctor about:
- new lumps
- new lumpiness
- changes in the shape of your breast
- changes in the colour of your breast
- changes in the nipple
- discharge from the nipple
- puckering or dimpling of breast skin
- any persistent breast pain
- any persistent nipple or breast itching or rash.
Last updated 01 November 2018 — Last reviewed 30 October 2018
This web page is designed to be informative and educational. It is not intended to provide specific medical advice or replace advice from your health practitioner. The information above is based on current medical knowledge, evidence and practice as at October 2018.