Abnormality of Breast Size

Abnormally large, small, or asymmetrical breasts

  • Develops during puberty
  • Genetics and lifestyle are not significant factors

There is considerable variation in breast size among women. A slight asymmetry in the size of the breasts in an individual woman is also common. However, having abnormally large, small, or asymmetrical breasts can lead to emotional distress and, in the case of very large breasts, may cause pain (see Breast pain) and discomfort.

Breasts that grow abnormally large often develop rapidly during puberty and are thought to be the result of oversensitivity of the breast tissue to the female sex hormone oestrogen. Large breasts may lead to pain in the back, shoulders, and neck, and in some cases a skin infection may develop under the breast. Women who have abnormally large breasts may experience discomfort when running or playing sports. They may also have difficulty in finding clothes that fit.

In some women, the breasts develop to only a very small size. A woman who has very small breasts may find her appearance unfeminine. However, having small breasts does not cause any physical problems and does not affect a woman’s ability to breast-feed.

Occasionally, there is a marked difference in size between the two breasts because one breast develops more than the other at puberty. This asymmetry may cause embarrassment and anxiety.

What might be done?

Women with large breasts can benefit from a well-fitting, supportive bra. You may also find that wearing a bra at night makes you feel more comfortable. If this does not relieve your discomfort or distress, you may wish to consider the possibility of a surgical operation to permanently reduce the size of your breasts (see Breast reduction).

Women with small breasts may find that a padded bra improves their body shape under clothes. The only permanent way to enlarge small breasts is by surgically inserting an implant behind the breast tissue. Breast implants consist of a flexible silicone shell filled either with silicone gel or with saline (a salt water solution).

Some women who experience distress as a result of having abnormally large, small, or asymmetrical breasts may find counselling of benefit.

Treatment: Breast Reduction

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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