Breast lumps and changes

Key points about breast lumps and changes

  • Most breast lumps are due to natural changes in your breasts during menstrual cycles, pregnancy, breastfeeding and ageing.
  • However, because 1 in 9 New Zealand women develop breast cancer in their lifetime, see your healthcare provider if you notice any changes in your breasts.
  • Most breast changes aren't cancerous but sometimes it is breast cancer.
  • Finding it early increases the chance of successful treatment.  
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Your breasts are made up of the following:

  • milk glands, which make breast milk and are made up of many milk sacs throughout your breast
  • milk ducts, which carry milk to your nipples
  • fibrous tissue, which covers and supports your whole breast
  • fatty tissue, which gives your breasts shape and size and supports the glands.

In your breast, armpit and neck there are also collections of lymph nodes. These are small glands, each about the size of a pea, that drain your breast of lymph fluid, helping your body fight infection and disease. Your chest muscles and ribs lie beneath your breasts. 

You may notice that your breasts are slightly different in shape or size or that one is slightly higher than the other – this is very common. If your breasts have always been like this, these differences are normal. 

Image credit: 123rf

To be breast aware, you need to:

  • know what is normal for you
  • know what changes to look and feel for
  • report any changes to your doctor straight away
  • go to mammography screening if you are between 45 and 69 years old
  • know your family history of cancer.

Look and feel for breast changes regularly, such as when dressing or showering, so that you get to know your breasts and how they change at different times of the month and as you age.

Video: Checked your breasts lately? We'll show you how.

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(Breast Cancer Foundation NZ, 2015)

If you notice any change in your breasts that is unusual for you see your doctor straightaway. For example:

  • a new lump or thickening
  • a change in breast shape or size
  • pain in your breast 
  • puckering or dimpling of your skin
  • any change in one nipple, such as a turned-in nipple or a discharge that occurs without squeezing
  • a rash or reddening of the skin that appears only on your breast. 

Although these changes do not necessarily mean you have breast cancer, any breast change should be checked by your doctor. Your doctor will examine your breasts and may refer you for a scan (ultrasound or mammogram). Read more about breast cancer

Most women have changes in their breasts during their lifetime. Many of these changes are caused by hormones. Other breast changes can be caused by the normal aging process.

Menstrual cycle – your breasts may feel more lumpy or tender at different times in your menstrual cycle. Before or during your menstrual periods, both of your breasts may feel swollen, tender or painful. You may also feel one or more lumps during this time because of extra fluid in your breasts. Wearing a supportive bra may be helpful. These changes usually go away by the end of your menstrual cycle.

Menopause – as you near menopause, your menstrual periods may come less frequently. Your hormone levels also change. This can make your breasts feel tender, even when you are not having your menstrual period. Your breasts may also feel more lumpy than they did before. They may also lose tissue and fat and become smaller and feel more lumpy.

Pregnancy – During pregnancy, your breasts may feel lumpy. This is usually because the glands that produce milk are increasing in number and getting larger in preparation for breastfeeding.

Breastfeeding – While breastfeeding, your breasts become full and firm with milk, then much softer after giving a feed. It is not uncommon to have tender breasts. You may get a condition called mastitis. This happens when a milk duct becomes blocked and leads to inflammation. Mastitis causes the breast to look red and feel lumpy, warm, and tender. Learn more about mastitis.

Hormone medications – If you are taking hormones (such as menopausal hormone therapy or birth control pills or injections) your breasts may become more dense.

All breast lumps should be checked by a doctor. Most breast lumps that develop before menopause are benign (not cancerous), but you need to get any lumps checked to rule out cancer.

Benign breast problems include pain, lumps or masses, infections, nipple discharge and skin changes. Common benign lumps include the following:

  • Lipomas – these are lumps made up of fatty tissue and can be found just under your skin anywhere on your body.
  • Cysts – these are fluid-filled sacs. You may have a single cyst or a number of different sized cysts. Your doctor may use a needle to remove the fluid in these.
  • Fibroadenomas – these lumps are smooth, hard and movable, rather like a marble dropped into your breast tissue. They are common in women aged 18–30.

Read more about benign breast conditions(external link)(external link) (Breast Cancer Foundation, NZ)

Breast self-examination is a formal, structured technique by which women feel for breast lumps and or changes on a regular basis, usually every month. 

This is no longer recommended, because:

  • there is no evidence that doing breast self-examination will reduce your chances of dying from breast cancer, and
  • it can lead to anxiety and unnecessary breast biopsies, particularly among younger women.

Instead, it's better to be breast aware as described above and to see your doctor to check out any lumps or changes that are unusual for you.

Breast awareness(external link)(external link) Breast Cancer Foundation, NZ
Breast screening(external link)(external link) Time to Screen, NZ
Breast lumps(external link)(external link) NHS, UK


Breast awareness – what you need to know(external link)(external link) Breast Cancer Foundation, NZ, 2019
Benign breast conditions – breast calcifications(external link) HealthEd, NZ, 2022
Breast pain (mastalgia) [PDF, 419 KB] CCDHB, NZ, 2018
Breastscreen Aotearoa – for Pacific women(external link)(external link) Breastscreen Aotearoa, NZ, 2015
Breast problems – swollen breasts(external link)(external link) La Leche League and Ministry of Health, NZ, 2018 English(external link)(external link), te reo Māori(external link)(external link), Samoan(external link)(external link), Tongan(external link)(external link), Niuean(external link)(external link)
Breast cancer: A guide for women with early breast cancer Cancer Society, NZ, 2011 Samoan(external link)(external link)


  1. Information on breast awareness(external link)(external link) National Screening Unit, Cancer Society, Breast Cancer Foundation, NZ, 2013
  2. Understanding breast changes – a health guide for women (external link)(external link) National Cancer Institute, US, 2014
  3. Benign breast problems and conditions(external link)(external link) The American College of Obstetricians and Gynecologists, US, 2021
  4. Benign breast conditions(external link)(external link) Breast Cancer Foundation, NZ
  5. Phelan ST. ACOG guidelines at a glance – diagnosis and management of benign breast disorders(external link)(external link) Contemporary OB/GYN, 2017

Breast awareness position statement(external link) NZ Breast Cancer Foundation, 2008
Information on breast awareness(external link) National Screening Unit, Cancer Society, Breast Cancer Foundation, NZ, 2013
Understanding breast changes – a health guide for women (external link) National Cancer Institute, US, 2014
Benign breast problems and conditions(external link) The American College of Obstetricians and Gynecologists, US, 2021
Benign breast conditions(external link) Breast Cancer Foundation, NZ
Phelan ST. ACOG guidelines at a glance – diagnosis and management of benign breast disorders(external link) Contemporary OB/GYN, 2017

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Credits: Healthify editorial team. Healthify is brought to you by Health Navigator Charitable Trust.

Reviewed by: Dr Phoebe Hunt, Auckland DHB

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