A note on terms:
Breast cancer can affect anybody, and everybody is welcome in CoppaFeel!’s community. We’re actively inclusive in our language and we ask people how they want to be described.
The word ‘chest’ is inclusive of all bodies and genders. When we need to be clinically accurate we use the word ‘breast’. You might prefer to call your chest something else, and that’s ok!
When we say breasts, we mean the part of your body from your rib cage up to your collarbone and armpits, including your nipples. This is where everyone has breast tissue, and people of all genders can get breast cancer. We often use the words ‘breasts’ and ‘chest’ in our breast cancer information.
The more you get to know your chest, the more you will become familiar with natural changes that can happen. All bodies are different, and you are the expert on what is normal for you. It is important to pay attention to any changes to your chest. If you notice any changes you are worried about, speak to your GP.
Changes During Puberty
Breasts usually develop between the ages of 9 and 16, but it can be normal for them to grow earlier or later. During this time, female breasts grow more fatty tissue and milk-producing glands. Breasts are usually fully grown by the age of 17, but it could take a little bit longer. As your breasts grow, you might feel aching or tingling. This is completely normal. There is nothing you can do to speed this up or slow it down. If you want to wear a bra to feel comfortable, wear one that fits you well. Some people gain weight during puberty, and that is completely normal. There is some fat in breast tissue so you might find your breasts grow if you put on weight. It is normal for your breasts to be slightly different sizes. After puberty you might notice hair around your nipples. That is completely normal too. If you would like to know more about puberty, our friends at Brook are health and wellbeing experts for young people. They can provide help and advice.
Monthly Changes
Breasts come in all shapes and sizes, and they will change throughout your life. Some breast lumps are perfectly normal, but if you get a new lump or an old lump comes back, contact your GP. It is important to get to know your normal monthly rhythm so you notice any unusual changes quickly.
If you have periods, you might find that your breasts naturally change as part of your monthly cycle. It is normal for your breasts to feel tender or sore around the time of your period. This is called cyclical pain and it is very common. Cyclical pain is caused by natural hormone changes and it is harmless. Breast pain on its own is rarely a sign of breast cancer. Read more about breast pain.
Changes During Pregnancy and Breastfeeding
It is normal for your breasts to change during pregnancy. Both pregnancy and breastfeeding cause breast changes because of pregnancy hormones. During pregnancy and breastfeeding you might notice the following changes to your breasts:
- Changes in size or shape
- Changes in skin colour
- Increased sensitivity
- Visible veins
It is important that you keep checking your chest during pregnancy. This is to help you get to know the natural changes that come and go. Breast cancer can happen during pregnancy and when you’re breastfeeding. If you are worried about any breast changes, talk to your GP or midwife. Read more about breast changes in pregnancy and breastfeeding.
Breast Changes in Men and Boys (Gynaecomastia)
If you have heard people talking about ‘man boobs’, they might be talking about a condition called gynaecomastia. Gynaecomastia is a common, benign (not cancer) condition that causes the breast tissue of men and boys to grow larger than normal. Due to increased hormones, it is common in teenage boys.It can happen in men of any age. In 9 out of 10 cases, gynaecomastia gets better on its own. Gynaecomastia might cause symptoms that are slight, extreme or in between. The chest area can be slightly sore to the touch. Although gynaecomastia is harmless, boys and men must get to know their chests and get any changes checked by a GP. Our friends at Breast Cancer Now have more information about gynaecomastia. If you are worried about this condition, please speak to your GP. Remember, this is a common condition and your GP has seen it all before, so don’t be embarrassed. Just get it checked.
Natural changes and breast cancer FAQs
How can I tell if a change is because of puberty or a sign of breast cancer? How do I know if it's a lump or my chest growing?
It’s important to get to know your own body, and what is normal for you. We encourage people to check their chest every month. Some lumps are perfectly normal, but if you get a new lump or a lump comes back, contact your GP.
Is it normal to have two different sized breasts?
It’s perfectly normal to have breasts of different sizes.
What's the normal breast size?
There is no ‘normal’ size, we are all one of a kind! Some people have one breast smaller than the other. Our bodies are always changing, and our chests will change too.
Is it normal for your chest to hurt when you’re on your period?
It’s normal for your chest to feel tender, sore or swollen around the time of your period. Get to know what is normal for you around the time of your period.
We suggest checking around the same time of the month, every month. If you notice any constant, unusual pain speak to your GP.
Signs and symptoms of breast cancer
Our health information has the PIF TICK quality mark, so you can trust and rely on it.
We updated this information in April 2024. We will look at it again in April 2027.