Mammals are the same characteristics of mammals, generally grow in pairs and are symmetrical on both sides. There is only one pair of human breasts in the chest, which comes from ectoderm. From birth, breast development has gone through different stages such as infancy, adolescence, sexual maturity, pregnancy, lactation and menopause. During the changes in different periods, the level of endocrine hormones in the body is very different, which affects the development and physiological function of the breast.
In infancy and neonatal period, because maternal estrogen can enter the baby through the placenta, breast tissue hyperplasia is caused. About 60% of newborns have 1 ~ 2 cm induration under the nipple 2 ~ 4 days after birth, and a small amount of milk-like substances are secreted. With the gradual metabolism of maternal hormones, this phenomenon can disappear on its own after birth 1 ~ 3 weeks. What needs to be pointed out here is not to squeeze the nipple by hand to avoid infection. It is a popular custom in some parts of China that all newborns will squeeze their nipples after birth, otherwise it will cause nipple depression. This kind of understanding is unscientific and the practice is not desirable. The reason of nipple depression is abnormal breast development in embryonic period, not because they have not squeezed nipples. In infancy, the breast is basically in a "static" state, the glands are degenerated, and men are more complete than women. From adolescence, influenced by various endocrine hormones, female breasts enter the most active period of physiological development and functional activities in their lives until menopause. After going through puberty, the organizational structure of the breast has tended to be perfect, and it has entered a sexually mature breast. In each menstrual cycle, with the periodic changes of ovarian endocrine hormones, breast tissue is also undergoing periodic changes of proliferation and rejuvenation. Pregnancy and breastfeeding are special physiological periods for women of childbearing age. At this time, a series of changes have taken place in the breast to meet this special physiological demand. Since menopause, endocrine hormones in the ovary have gradually decreased, and the physiological activities of the breast have weakened.
In female adolescence, the earliest and most obvious secondary sexual characteristics are breast development and rapid physical growth, and breast development is often the most obvious starting point of adolescent sexual development.
Adolescent girls will first notice the prominent nipple development. With the development of the breast, fat and blood vessels increase, making the whole breast bulge. This change can be seen from the appearance. At the same time, the brown areola around the nipple gradually expands and the breast develops completely. About 80% of girls don't approach adults until 16- 19 years old.
In addition to hormones, breast development is also affected by genetic factors. Another feature of breast development is that in the early stage of development, one breast may be significantly larger than the other. With the development, it gradually tends to be equal or basically equal. After breast development is basically finalized, girls should wear bras in time. Wearing a bra can support and support the breast, make the blood circulation of the breast smooth, be beneficial to the development of the breast, protect the nipple from abrasion and pain, and keep warm in autumn and winter. Choose a bra with the right size. It should be comfortable and not tight after wearing it. It should also be replaced at any time according to the changes in body fat and thin. You can't wear an inappropriate bra because of the pursuit of beauty. When should I start wearing a bra? See >>
Adolescent girls seldom breastfeed.
Breast development does not secrete milk. The reason should start from the source of prolactin, which is produced by an endocrine gland called pituitary gland (about one gram in size and shaped like broad bean) in the human brain, but it is also controlled by prolactin inhibitor secreted by hypothalamus, which inhibits the secretion of prolactin by pituitary gland, so lactation is a special function of maternal parenting. Women in general, especially adolescent girls, do not have lactation function.
Breastfeeding is an abnormal phenomenon.
There are two reasons for this abnormal phenomenon: first, prolactin gonadal tumor occurs in pituitary gland; Second, although there is no prolactin tumor, because pituitary cells are stimulated by prolactin promoting factors secreted by hypothalamus, prolactin secretion is excessive, which is called hyperprolactinemia.
In addition to galactorrhea, patients with hyperprolactinemia are often accompanied by menstrual disorders of different degrees. In severe cases, symptoms such as amenorrhea, alopecia, weight gain, headache, visual impairment and atrophy of external genitalia even occur, forming a group of diseases characterized by galactorrhea, amenorrhea and infertility, also known as "galactorrhea-amenorrhea syndrome". However, regardless of the severity of symptoms, the main reason is excessive prolactin production. There are many reasons for hyperprolactinemia, which can be roughly divided into the following categories: hypothalamic disorder, pituitary disorder, primary hypothyroidism, drug factors, nerve stimulation and so on. Read in detail >>& gt& gt
The diagnosis can be further confirmed by head CT photos or MRI vibration photos and serum prolactin content determination. If there is a tumor that can be treated with gamma knife, it can be cured without craniotomy: if it is not a tumor, it is only hyperprolactinemia, so it is ok to take medicine according to the symptoms, but it must be taken under the guidance of a doctor.
Learn to introspect breasts.
Before the ovary secretes progesterone, the development of glandular lobules is extremely limited. After sexual maturity, especially during pregnancy, under the combined repeated action of progesterone and estrogen, glandular lobules can fully develop. The development of glandular lobules requires a certain intensity of hormone stimulation and an appropriate proportion of estrogen and progesterone, otherwise the epithelial cells of the terminal mammary duct are prone to abnormalities, such as cystic hyperplasia.
Therefore, it is particularly important to check whether there will be problems with your breasts at this time. Here, Bian Xiao will teach you two tricks and learn to check your breasts. Six steps of chest self-examination
Bian Xiao's conclusion: From this incident, young parents are reminded not to take their children's physical abnormalities for granted, but also to think from the perspective of physical health. Taking a child to a specialist examination will definitely make many things clear, otherwise guessing and asking questions will affect the good feelings with the child, and it is more likely to miss the best opportunity for disease diagnosis and treatment.
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