Blog post —
Why exercise won't get rid of accessory breast & How hormonal changes affect its size
Updated on: April 1, 2026
Axillary breast tissue, also known as accessory breasts, is found in approximately 6 percent of the female population.
A lesser-known fact is that they are also found in 1% to 3% of the male population!
The presence of these tissues can cause discomfort and pain.
Generally, accessory breasts are benign, but there have been cases where the lumps are cancerous.
It's best to diagnose the problem so that the proper treatment can be applied.
What Is Accessory Breast Tissue?
Accessory breast tissue is defined as "residual breast tissue that persists from normal embryologic development."
An accessory breast develops outside the breast area and is deceptive as it may remain undetected until the individual reaches puberty.
It is most commonly located in the armpit, but locations outside the milk line, including the:
- face
- neck
- chest
- middle back
- buttock
- genitals
- flank
- hip
- shoulder
- arms
- thigh
Accessory breast tissue can contain all or partial elements present in normal breast tissue — glands, areola, and nipple.
According to medical classification, there are 8 different possible subtypes of the accessory breast [2]:
- Complete breast with nipple, areola and glandular tissue
- Supernumerary breast without areola
- Supernumerary breast without nipple
- Aberrant glandular tissue only
- Nipple and areola with fat (pseudomamma)
- Nipple only
- Areola only
- Hair only
The presence of extra breast tissue is not only a cosmetic concern.
Depending on its size, it can also cause discomfort and pain, making wearing certain clothing an ordeal.
What Causes Accessory Breast Tissue?
A patient with accessory breast tissue may be asymptomatic and unaware of the presence of accessory breast tissue.
Accessory breast tissue, like a normal breast, responds to hormonal influences.
It may come to attention during changes in estrogen and progesterone levels which can cause the breasts to swell, often during pregnancy, lactation or before menstruation.
There may be certain genetic influences for certain susceptible individuals, but for most, there are no identifiable risk factors that lead to the development of accessory breasts.
How accessory breast tissue responds to various life stages and hormonal changes
Period |
How hormone changes during this period affect accessory breast |
|---|---|
Puberty |
Estrogen is responsible for breast development. During puberty, an increase in this hormone may also stimulate the growth of accessory breast tissue. |
Menstrual cycles |
Throughout the menstrual cycle, levels of estrogen and progesterone (the hormones that regulate the menstrual cycle and pregnancy) fluctuate, affecting breast tissue and sometimes causing pain or swelling. |
Pregnancy |
During pregnancy, levels of prolactin (a hormone responsible for stimulating milk production), estrogen, and progesterone increase, resulting in substantial growth of both normal and accessory breast tissue. |
Lactation |
Levels of prolactin, estrogen, and progesterone hormones rise during breastfeeding. This may encourage further growth in accessory breast tissue enlargement and might cause discomfort or even pain. |
Menopause |
During menopause, hormonal changes can change the appearance and texture of breast tissue (normal and accessory). |
Intake of Hormonal contraceptives and Hormone Replacement Therapy (HRT) |
Hormonal contraceptives, like birth control pills, can increase breast size temporarily as they increase estrogen and progesterone levels. This can also cause the surrounding breast tissue to swell or become more noticeable. HRT includes estrogen and progestin. These hormones can cause the breast tissue to become denser. This change can also impact mammogram reading and how it displays breast tissue. Individual responses vary. Some women might notice clear changes, while others might not see any difference. |
Accessory breast tissue undergoes age-related changes similar to those of normal breast tissue, including being susceptible to female breast cancer.
We recommend performing regular self-examinations and undergoing thorough annual clinical breast exams and mammograms, especially if any abnormalities are detected.
Read more about how accessory breasts affects pregnancy and postpartum mothers:
- Armpit lumps & axillary accessory breasts during pregnancy
- Accessory breast tissue in pregnant and postpartum mums
- Mother of 2, Breast Enhancement With Fat Grafting And Accessory Breasts Removal
- 40-year-old homemaker removes accessory breasts she had since puberty
FACT! Exercise Won't Get Rid Of Accessory Breast
Targeted Workout For Axillary Breast Tissue Is A Myth
Persons with accessory breasts are often misdiagnosed to have excess armpit fat. Treatment for accessory breasts and 'armpit fat' are very different.
The main reason weight loss and exercise are not of much help for accessory breasts is due to the presence of breast tissue and, in some cases, excess skin tissue.
Weight loss or exercise will not affect these tissues very much.
Surgery can relieve the symptoms for those who are affected.
The Permanent Option
The most important thing when it comes to accessory breast tissue is to have it properly diagnosed, as it can be mistaken for underarm fat. This can lead to the wrong procedure being performed.
Treatment options will depend on the size and shape, the location, the amount of loose skin tissues and the subtypes of the accessory breasts present.
Treatment may include microscopic surgery, liposuction, skin tightening and others. If done properly, surgery offers a permanent option for people who suffer from this condition.
Are you considering accessory breast removal? Contact Amaris B. today!
Reference
- Bhave, M. A. (2016). Axillary Breast: Contouring the Axilla. In Body Contouring and Sculpting. IntechOpen.
- Aydogan F, Baghaki S, Celik V, et al. Surgical treatment of axillary accessory breasts. Am Surg. 2010;76:270–2.