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Breast Development During Puberty: Issues, Sizes, How to Choose a Bra, and More!

For teens, puberty is when most physiological changes occur. It’s when rapid growth and development happens, mainly due to hormonal changes. Puberty is characterized by the development of breasts in the female body. This is one of the most noticeable changes in the body. In this article, we’ll let you in on everything you need to know about teen breasts and the best way to handle your changing body.

Breast development in puberty

In the female body, puberty usually starts between the ages of eight and 13, although some will start puberty much earlier or later. Generally speaking, though, it usually starts during the middle school or high school years. 

During puberty, there’s a natural increase in the hormone estrogen in the body. This is the hormone responsible for the changes that occur during adolescence, including developing breasts. There may be more changes happening in your body, but breast development is often the first thing people notice as they go through puberty

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As they develop, breasts typically begin as a small mass under the nipples, like a mound or a nub that will continue to grow over time. Once you feel ready to wear a bra, ask a parent or trusted guardian to help you choose one that’s comfy. You can also skip wearing a bra if you prefer.

Normal teen breasts: What do they look like?

In the early stages of development, breasts appear as small nubs or lumps that are called breast buds. This usually happens somewhere between the ages of eight and 13, with significant variation among individuals. Breasts continue to progress until they are fully matured. Normally, full breast maturation takes three to five years. 

When breasts start to bud, they first appear as a firm bump underneath the nipple. The areola may also grow bigger along with the nipple itself.

Puberty breast development stages

Breast development during puberty occurs in stages:

  • First stage — In the first stage (during childhood), the breasts are flat. 
  • Early breast development — Breast development usually occurs two to three years before the first menstruation. This is characterized by the appearance of breast buds. During this stage, the nipple and surrounding area (called the areola) start to expand. Breast tissue starts to develop, and the breasts are hardly noticeable and hard to the touch.
  • Breast enlargement — The breasts start to enlarge into a conical shape at first, then into a rounder shape. In this stage, the areola darkens and expands, while the nipples may grow more pointed. 

It’s also pretty common for one breast to grow faster than the other.

How to change breast size and shape

Breast size and shape vary. The size of your breasts will largely depend on genetics, so if larger breasts run in the family, then you have a good chance of developing larger breasts as well. It’s important to make sure you take care of your breasts, especially during an important time like puberty. In this stage, the breasts are continuously growing, and neglecting them may cause problems. 

Large-breasted teens may find it difficult to get used to their growing breasts, and some small-breasted teens may wonder what factors affect their growth. 

Puberty breast development is a natural process, and there isn’t much you can do to influence it. Let’s dive into why some breast-changing methods may or may not work.

Discover 4 ways to make puberty a little easier.
A girl choosing a bra for teen breasts

Pills and creams

Catchy ads for creams and pills often claim they can make breasts bigger or smaller. However, this is far from the truth and might even be unsafe for your health. Unapproved pills and creams may contain chemicals that are not safe for your skin or your health in general, so using them is highly discouraged. 


No form of massage can affect the size of breasts. If you overdo it, it might even hurt or irritate your skin and nipples.


Breasts are mainly made up of fatty tissue rather than muscle, so exercise won’t affect breast development. However, exercise can improve your health.

Weight change

Losing or putting on weight may affect breast size, but it doesn’t always do so.

It’s natural to put on weight in your teenage years. It’s essential to have a certain percentage of body fat, so this shouldn't cause any concerns. Just like other parts of your body, breasts contain fatty tissue. That's why gaining weight may increase the size of the breasts, and losing weight might make them a bit smaller.

Sleeping on your stomach

Sleeping on your stomach won’t affect teenage breast development or make them smaller. However, if your breasts are feeling sore, you might find it more comfortable to sleep on your back or side.

Sleeping in a bra

Sleeping in a bra has its own pros and cons, but it's definitely not known to change breast size or shape. Some people may feel more comfortable sleeping in a bra: if so, it’s usually recommended to wear a light bra without an underwire while you sleep so that your breasts are not compressed and blood circulation is good. 


Resorting to surgery to change the size or shape of the breasts is not an option under a certain age. According to the FDA, breast augmentation surgery is not recommended before the age of 18, and breast implants have a minimum appropriate age of 22.

Puberty breast problems

It’s normal to experience tenderness or pain in growing breasts, particularly in the nipple area. These growing pains are part of teen breast development and can be managed with the right bra. It is important that you ask someone with experience to help you choose the correct size and style of bra, especially if you are experiencing soreness. 

Something lots of teens wonder is, can teenagers get breast cancer? It’s very unlikely to develop breast cancer under the age of 30. Breast cancer in teens is extremely rare.

When to see a health care provider?

Lumps in developing breasts are normal. If you feel a hard lump underneath your breasts that causes you concern, or if your breasts become hot to the touch or red, your body temperature rises, or you feel sick and unwell, go to a health care provider or a school nurse. Everything is probably fine, but it’s also good to check out any painful lumps.

How to choose a bra when you're a teenager

If you notice your breast buds poking through your shirt, you may want to get your first bra, often called a “training bra.” A training bra can ease the pain associated with breast development and help you feel comfortable. Training bras are typically made out of soft cotton without cups and are very easy to wear.

Once breasts have developed further, it may be time to consider getting a soft cup bra. These are similar to training bras, but they have soft cups to keep the breasts comfortably in place. However, underwire bras and other complicated bras aren’t recommended. Instead, choose a bra that will be comfortable and won’t worsen any growing pains.

As breast growth continues, you can choose more appropriate bras that would fit you while still being comfortable. Make sure they fit properly: a bra that’s too small would constrict your chest and prevent proper breast development. On the other hand, bras that are too big may be awkward and uncomfortable to wear.

Puberty 101
Read medically reviewed articles on topics like first period, hormonal changes during your cycle, female anatomy and speaking to a parent about puberty.

How to handle breast changes

Breast development can be exciting and confusing at the same time. Nevertheless, it is important to remember that this process is a perfectly normal part of growing up. It’s normal to feel confused by the changes in your body, but learning how to handle these changes can help.

If you are feeling self-conscious or you’re not that comfortable with the size of your breasts, find a trusted adult you feel comfortable talking to about it. Your mom, your aunt, a big sister — talk to them about your problems, how you feel, and how they can help you be more comfortable with the process. Remember, it’s best to talk about your feelings rather than keeping them bottled up.

If you feel like you need support getting through puberty, that’s perfectly fine! Your family and close friends can be a support system to help you when you need it. There’s no need to go through these formative years on your own instead of sharing your experience and feelings with people who care about you.


Puberty is a huge change that has physical, emotional, and mental effects. Once puberty starts, hormones can cause drastic changes in the body. Some of the most notable are: wider hips, narrower waist, body hair, increased sweating, acne, increased height and weight, and breast development.

If your breasts have started to develop, it may be time to learn more about the changes happening in your body.

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