The female breast

Synonyms in a broader sense

Mammary gland, mamma, mastos, mastodynia, mastopathy, mammary carcinoma, breast cancer

English: female breast, mamma


The female breast consists of glands (glandula mammaria), fat and connective tissue. From the outside you can distinguish the breast, the nipple and the surrounding atrium. It is used for the milk production and nutrition of the infant.

Female Breast Anatomy

Anatomically, the breast can be divided into 10 to 12 lobes (lobi). One mammary gland is located in each of these flaps. This consists of several end pieces that together form a lobule (lobule). A lobe is divided into several lobes. The end pieces have a connection to a small duct (terminal duct, ductus terminalis). These small ducts of the end pieces join together to form several somewhat larger ducts (ductus lactiferi). And the somewhat larger ducts ultimately lead to a main duct (ductus lactifer colligens), which widens at the end (terminal). This expansion is called a sine. The sinuses have a connection to the nipple (papilla mammaria).

The breast (mamma) lies directly below the skin and the subcutaneous fat tissue on the pectoral muscle (musculus pectoralis). The breast is supplied with nutrients from several small vessels (arteries) that originate from the arteries between the ribs (intercostal arteries = arteriae intercostales). The lymph vessels lead to lymph nodes that are located in the armpit (Nodi lymphatici axillares), on and in the chest muscle (Nodi lymphatici pectorales et interpectorales), in the spaces between the ribs (Nodi lymphatici intercostales) and on the lateral edge of the mammary gland (Nodi lymphatici paramammarii).

Figure female breast

Illustration of the mammary gland of a young woman: vertical section through the nipple (A) and muscles of the anterior chest wall from the left (B)
  1. Nipple -
    Papilla mammaria
  2. Areola -
    Areola mammae
  3. Milk duct -
    Lactifer duct
  4. Lobule of the mammary gland -
    Lobuli glandulae mammariae
  5. Adipose tissue -
    Corpus adiposum mammae
  6. Ribs - Costas
  7. Pectoralis major -
    Pectoralis major muscle
  8. Anterior saw muscle -
    M. serratus anterior
  9. Outer weird
    Abdominal muscles -
    Obliquus muscle
    externus abdominis
  10. Chest wall - thorax
  11. Skin - Cutis

You can find an overview of all Dr-Gumpert images at: medical illustrations

Development and function

The female breast begins to develop at the beginning of puberty.
From the 10th / 11th year of life onwards, the mammary gland grows more rapidly. According to this, there are fewer glands in the child than in the sexually mature woman.
Upon completion of the puberty the woman has therefore only reached the maximum number of mammary glands.

However, unless you are pregnant or breastfeeding, the mammary glands are not fully developed. The end pieces are rather small and the connective and fatty tissue predominates (dominates) proportionally.

Only when one pregnancy and then the lactation period (see Breastfeeding) are present, the lobules enlarge compared to the resting state. The end pieces widen and have large spaces (lumens) filled with milk.
The fat and connective tissue is greatly reduced.

This process is carried out by Hormones the Pituitary gland (Pituitary gland) controlled. If there is no pregnancy, there is no hormonal influence (the hormonal stimulus) and there is no development of the mammary glands.

In the case of pregnancy, there are high levels of sex hormones that the mammary glands develop. The hormone progesterone for the Growth (proliferation) and Training (differentiation) of the end pieces. By the influence of the hormone estrogen there is a growth in the execution aisles.
This hormonal influence on the breast begins right in the first three months of pregnancy (first trimester). So the breast unfolds more and more during pregnancy. Nevertheless, there is no formation of milk during pregnancy and therefore no release (secretion) of milk through the nipple.
This is because the high levels of the hormone progesterone suppress the release (secretion) of two other hormones. These other hormones are Prolactin and oxytocin, also hormones from the pituitary gland.

Prolactin is responsible that Breast milk is formed in the end pieces. This hormone is only released (secreted) when the woman has given birth to her child and the high level of progesterone, which is needed to maintain the pregnancy, drops. Only then can prolactin be secreted in the first place. The infant itself gives the necessary impulse to secrete prolactin by sucking on the breast. This tells the pituitary gland that it needs prolactin and releases the hormone.

Oxytocin is necessary for the milk from the end pieces to get into the main discharge duct and then into the nipple and reach the infant. It is therefore responsible for expelling (ejection) the milk. In doing so, it does nothing but influence (stimulate) small muscles (myoepithelia) that are arranged around the cells of the end pieces and excretory ducts. As a result of this influence (stimulation), the muscles contract (contract) and the milk is conducted from the end pieces via the small and large ducts to the main duct and sinus, in which the milk can collect.
The stimulus for the release of the hormone is also the suckling of the baby on the nipple. The so-called touching stimulus (tactile stimulus) thus triggers the complete reflex to release the Breast milk (milk ejection reflex) out.

These two hormones are secreted as long as the infant is breastfed. During this time, the hormone prolactin also suppresses the Menstrual cyclein which it inhibits the sex hormones required for this. So it usually comes to the absence of breastfeeding Menstrual period (secondary amenorrhea).

Only when the tactile stimulus disappears does the milk ejection reflex disappear. The mammary gland is then restored to its previous state of rest and the hormones in the body change in such a way that menstrual periods start again.

With a decrease in sex hormones (estrogen, progesterone) in and after the Menopause (peri- and postmenopausal), there is a regression or "shrinkage" (age atrophy) of the mammary gland. The lobules become smaller (atrophic), the fat percentage of the breast increases.

Female Breast Disorders

Important diseases are the Breast cancer and the Mastopathy.
The Ultrasonic, the Mamography and the MRI of the chest available.

You can find extensive information on the diseases at Female Breast Disorders.


Benign changes in breast tissue (Connective and / or glandular tissue) (Mastopathy) are the most common diseases of the chest. 40-50% of all women suffer from it. These are changes in which there is a hormone-dependent increased growth (proliferation) and withdrawal (regression) of the breast tissue.

Some women, mostly from the age of 30, also have cycle-dependent problems Chest pain (Mastodynia).

A bilateral milk release from the mammary gland outside of pregnancy and lactation (galactorrhea) also has a disease value. This condition can have many causes. For example, there may be a hormonal disorder. Furthermore, such a disease can also occur as a concomitant disease in connection with other diseases. And also stress or heavy physical work can trigger galactorrhea (milk flow).

Benign tumors in the breast (breast tumors) can be connective tissue tumors with a glandular portion (fibroadenoma), cysts or tumors made of fat (lipoma).

The breast can also be inflamed (non-puerperal mastitis). The reason for such breast inflammation can be bacteria (bacterial mastitis non-puerperalis) and, for example, disturbed hormone levels in the body (abacterial mastitis non-puerperalis).

You can find out more about this under our topic: Mastopathy

Breast cancer

The Breast cancer (breast cancer, Mum Ca) is the most common cancer (malignant tumor) in women and is an important disease of the breast. Women are often affected after the menopause (around the age of 50). But younger women around the age of 20 can also develop breast cancer. Men can also participate Breast cancer get sick!

The places where breast cancer often forms (predilection point) are the end pieces of the mammary gland and the duct that adjoins the end pieces (terminal duct = ductus terminalis). How to distinguish a breast cancer of the lobule in which the End pieces are located (lobular breast carcinoma) from a breast cancer the Excretory ducts (ductal breast carcinoma).
The localization is divided into 4 quadrants and nipple a (see picture above)
Further and very extensive information on this topic can be found under our topic: Breast cancer

The male breast

The male chest basically has the same structure as a woman's breast. However, it will remain at the level of a child for a lifetime, at least if there is no disease that affects the growth of the mammary gland. The mammary glands are not as numerous as in women. The existing ones are also small and not unfolded and are rather sparsely represented in comparison to the connective and fatty tissue, which is also present in a smaller proportion than in women.