What is the function of female breasts?

Breast is mainly composed of glands, ducts, adipose tissue and fibrous tissue.

The mammary gland consists of 15 ~ 20 gland lobes, each gland lobe is divided into several gland lobules, and each gland lobule consists of 10 ~ 100 acinus. The acinus is closely arranged around the small mammary duct, and its opening is connected with the small mammary duct. Many small mammary ducts converge into interlobular mammary ducts, and many interlobular mammary ducts converge into a whole glandular breast duct, also known as mammary duct. There are * * * 15 ~ 20 milk tubes, which are radially arranged around the nipple and converge in the areola, and the opening is located in the nipple, which is called the feeding hole. The ductus lactis narrows at the nipple and then expands into ampulla, which is called ductus lactis sinus and can store milk. The opening of mammary duct is stratified squamous epithelial cells, and the stenosis is transitional epithelium. The ducts at all levels below ampulla are double-layer columnar epithelium or single-layer columnar epithelium, and the terminal ducts are cubic epithelium near acinus, which is lined with cubic epithelium. The adipose tissue in the breast is wrapped around the breast to form a hemispherical whole. This layer of adipose tissue is called the adipose capsule. Due to age, fertility and other reasons, the thickness of fat sac may vary greatly among individuals. The amount of adipose tissue is one of the important factors that determine breast size.

2, the external structure of the breast

The nipple is composed of dense connective tissue and smooth muscle. Smooth muscles are arranged in a ring or radial pattern. When there is mechanical stimulation, the smooth muscle contracts, which can make the nipple erect and squeeze the catheter and feeding sinus to discharge its contents. There are hairs and glands on the skin of areola. Glands are sweat glands, sebaceous glands and mammary glands. Its sebaceous gland, also known as areola gland, is large and superficial, and its secretion has the functions of protecting skin, lubricating nipple and baby's lips.

The breast is located between the superficial and deep layers of the superficial fascia under the skin. Superficial fascia extends into breast tissue to form interlobular septum, and one end is connected with pectoral fascia. The other end is connected with the skin to fix the breast in the subcutaneous tissue of the chest. These fibrous connective tissues that support and fix the position of the breast are called suspensory ligaments of the breast. The deep layer of superficial fascia is located in the deep layer of breast and connected with the superficial layer of pectoralis major fascia through loose tissue. Can make the breast relatively fixed and have a certain degree of mobility on the chest wall. Sometimes, some mammary glands can penetrate loose tissues and go deep into the superficial layer of pectoralis major. Therefore, the fascia and muscle of pectoralis major should be removed together during radical mastectomy.

There are obvious changes in breasts during sexual excitement. Nipple tilt is a feature of female sexual excitement. When women are sexually excited, the breasts are completely erect, the superficial veins of the breasts are more clearly visible due to congestion, and the nipples are enlarged. Breast enlargement of non-breast-fed women can reach 20-25% of the original volume. The breast enlargement of women with breastfeeding experience is not obvious, but the redness and swelling formed by breast congestion can be seen.

Some people think that women with full breasts can get more pleasure in sexual life, which has no scientific basis. The size of breasts depends on heredity, acquired exercise, weight and many other factors. The size of breasts is not directly related to sexual pleasure and fertility.

1. The position and morphological structure of children's and men's breasts are underdeveloped, and the breasts of adolescent lactating women are hemispherical. It is located at the height of the second to sixth ribs, between the superficial and deep layers of the superficial fascia, on the surface of the pectoral muscle fascia, and can reach the axillary midline outward from the parasternal line. Breast contains breast and fat. The mammary gland is divided into 15 ~ 20 gland lobes by connective tissue, and each gland lobe is divided into several lobules. Each glandular lobe has a mammary duct, which is arranged radially around the nipple and ends at the nipple. When breast abscess is cut and drained, radial incision should be made to avoid cutting off the mammary duct, and the connective tissue interval should be separated to facilitate drainage. There are many fiber bundles perpendicular to the skin in the connective tissue between glandular lobes, one end of which is connected with the superficial skin and superficial fascia, and the other end is connected with the deep superficial fascia, which is called suspensory ligament of breast or Cooper ligament. Because both ends of the ligament are fixed and not extensible, when breast cancer occurs, the skin there is sunken. There is a gap between the superficial fascia and the pectoral fascia, which is called the posterior mammary space. It contains loose connective tissue, fat and lymphatic vessels, which receive lymph deep in the breast. When breast cancer occurs, lymph can transfer to the deep. This gap tends to expand downward when it is inflamed, which is suitable for low incision and drainage.

2. There are abundant lymphatic vessels in women's breasts with lymphatic reflux, which are divided into shallow and deep groups. The superficial group is located in intradermal and subcutaneous, while the deep group is located around the lobule of breast and in the wall of mammary duct, which are widely consistent. The lymph of the breast is mainly injected into the axillary lymph nodes, and some of them are removed from the paraosseous lymph nodes, parapectoral lymph nodes and septal lymph nodes of the thoracic spine.

(1) Lymphatic vessels in the lateral and central parts of the breast are injected into the thoracic lymph nodes of axillary lymph nodes, which is the main way of breast lymphatic reflux.

(2) Lymphatic vessels in the upper part of the breast are injected into axillary lymph nodes and the top lymph nodes of supraclavicular lymph nodes.

(3) The lymphatic vessels of the inner breast are injected into the parasternal lymph nodes, which are consistent with those of the contralateral breast.

(4) The lymphatic vessels in the lower part of the breast are injected into the lymph nodes in the diaphragm, which are consistent with the lymphatic vessels in the upper part of the anterior abdominal wall and the diaphragm, thus indirectly connecting with the lymphatic vessels in the liver.

(5) Lymphatic vessels in the deep breast are injected into intercostal lymph nodes or apical lymph nodes through the posterior breast space and pectoralis major muscle. Intercostal lymph nodes, also known as Rotter node, are located between major muscles and minor muscles in the chest, and are usually involved in breast cancer. The superficial lymphatic network of the breast is widely anastomosed and the two sides are connected. When breast cancer involves superficial lymphatic vessels, it can lead to lymphatic reflux obstruction in the aggregation area, lymphedema, punctate depression and orange peel-like changes in local skin, which is an important basis for breast cancer diagnosis.

Sexual physiological response of female breast

Breast is an important symbol of women's sexual maturity, one of the most sensitive parts of women, and also an organ that secretes milk and nurtures offspring. Breast is a symbol of motherhood for children; For men, it is the object of hunger and thirst for beauty. Therefore, women in movies, TV, pictorial and literary works always have full breasts. Breast is an important sexual organ of women, and it also plays an important role in sexual activities, but people often ignore this point. The nerve distribution and the number of nerve endings in the breast are very rich, and the breast is closely related to other sexual organs.

During the exciting period of the sexual response cycle, the first evidence that the breast's response to sexual tension is enhanced is the erection response of the nipple, which is the result of the involuntary contraction of the abundant smooth muscle fibers in the nipple after sexual stimulation. The reaction of two nipples often does not happen at the same time. One nipple may have been completely erect and swollen, while the other nipple has lagged behind. An invaginated nipple may protrude from its resting state as if it were in a semi-erect state. If this invagination is difficult to recover, there is no indication of nipple reaction.

Adequate erectile response can increase the nipple length by 0.5- 1.0 cm, and the reaction can also increase the nipple base diameter by 0.25-0.5 cm. Generally, people with large nipples and protruding forward have less swelling and erectile tendency than people of normal size. The nipple is very small and it is difficult to react strongly to sexual stimulation, but it is rare that the nipple is very small.

The second physiological change in the exciting period is the delimitation and expansion of the breast vein tree model. If the breast has enough volume, there will be superficial venous congestion below, but it is likely to become more clear in the later stage of excitement. Larger breasts usually have obvious vein tree dilatation. When the congestion of mammary vein tree expands towards the center, it usually does not reach the areola area.

When approaching the plateau, the actual volume of the breast will increase obviously, which is the result of the deep vein congestion reaction of the breast. When there is an erectile response, the congestion in the lower part of the hanging breast is easier to observe. If the woman takes the supine position, the overall increase in breast volume will be more obvious. In the late stage of excitement, obvious areola congestion can be seen. The expression degree and occurrence time of excitement reaction vary greatly, and often vary from person to person. During the platform period, the areola near the upright nipple will also swell, which often gives people the illusion that the upright nipple has partially subsided. It is not until the areola swelling subsides during the regression period that people can see the nipples that subside late but remain erect again.

Before a woman experiences the last orgasm impulse, the breast size of a woman who doesn't drink water can increase by 1/5- 1/4, while the breast size of a woman who breastfeeds usually doesn't increase significantly. This anatomical difference may be due to the increase of venous shunt during breast milk production. Infant sucking will increase venous shunt and tend to slow down the congestion reaction of deep blood vessels during sexual tension. Obviously, the increase of breast size under the influence of sexual tension is not only related to the physiological reaction of blood vessel congestion, but also related to the fullness of fiber tissue components that constitute breast lobules. Hyperdilatation of the breast is common in early lactation, which will damage the effectiveness of these supporting fibrous tissues. Therefore, it can be understood that it is difficult for lactating women to respond obviously to sexual stimulation.

After sexual tension enters the plateau, pink spots often appear on the front, side and even bottom of the breast. In fact, this patchy rash first appeared in the upper abdomen and then spread to the surface of the breast. This blood vessel congestion reaction on the skin surface is called sexual blushing.

There is no special reaction in the breasts during orgasm. It has been confirmed that nipple erection and areola swelling, venous tree process is very eye-catching, breast without breastfeeding has obvious expansion compared with the baseline before stimulation, and sexual blush is very clear. The breasts will even tremble.

The arrival of the regression period is marked by the rapid regression of sexual flushing and the disappearance of synchronous areola swelling. However, the nipple erection subsided slowly. When the areola swelling subsided, the nipple erection became conspicuous again, giving people the feeling that it was a secondary erection reaction caused by new stimulation or acquired stimulation. People call this illusion "false erection".

Generally speaking, the deep vascular congestion of breast that has not been suckled subsides slowly, while the congestion of breast that has been suckled subsides quickly. It is often seen that breast swelling lasts for 5- 10 minutes after orgasm, and the superficial vein tree on the breast surface can even last for a long time. Before the venous trees completely return to their normal unexposed state, the upright nipples have completely recovered. The persistence of superficial and deep vascular congestion is a unique phenomenon of breast failure, which may be caused by excessive expansion of areola venous plexus in platform period. In the degenerative stage, this excessive expansion of venous plexus leads to slow blood flow from venous drainage to deeper veins.

The swelling and development of areola during pregnancy is an early feature of pregnancy influence. After pregnancy 1 month, there will be obvious vein tree distribution on the breast surface, which will run through the whole pregnancy and postpartum. A woman who is pregnant for the first time will have a sensitive area on one side of her breast, and the scope of this sensitive area will expand with the progress of pregnancy. After three months of pregnancy, the breast volume will increase rapidly, which is the result of the obvious increase of breast blood vessels and glands. After receiving sexual stimulation during pregnancy, women who are pregnant for the first time will have severe breast tenderness at orgasm, especially nipple and areola swelling. By the third month of pregnancy, this breast tenderness will be significantly reduced. Because the breast has shown the characteristics of conical lactation in the third trimester of pregnancy, and its volume has increased by about 1/3 compared with that in the non-pregnancy stage, high-level sexual tension often cannot make the breast volume increase further obviously. However, nipple erection and areola swelling reactions exist throughout pregnancy.

In the second and third months after delivery, the breast's response to sexual stimulation depends on whether it is breastfeeding or not. If the production of milk is artificially inhibited by hormone control or restraint oppression, other sexual reactions of the breast will be obviously inhibited, even when sexual tension reaches a plateau. It was not until 6 months after delivery that these women's breast sexual response was restored.

Although the breast size of lactating women does not increase significantly during sexual response, they often have unusual reactions. Many lactating women are often unable to control their milk when responding to sexual stimulation. During or after orgasm, milk can overflow from bilateral nipples, not only during sexual intercourse, but also during masturbation.

Six sources of breast pain

Being a woman is "good", but many women often feel breast pain. To sum up, there are six main types of female breast enhancement.