What happens to breasts during pregnancy?
What happens to breasts during pregnancy?
If you think that breasts grow only in youth, you are mistaken! The complex internal structures necessary for feeding the baby begin to form only during pregnancy, and until recently, we did not even imagine how this happens.
Have you ever thought about your breast during pregnancy? Surely only in the context of buying a special bra. Meanwhile, huge changes are taking place in the chest at this time. Not only the uterus, but also the breast undergoes an amazing transformation in order to prepare for the birth of the baby. But to figure it out, let’s go back a little …
Breast development in adolescence
The chest is constantly changing from adolescence to menopause. Unlike other organs, it does not grow until it is “activated” by hormones produced during puberty. However, even when the breast seems to have fully developed, it has not yet matured.
“After puberty is completed, the female breast continues to develop. With each cycle, the amount of secretory [milk-producing] tissue in it increases slightly, and this lasts until about 35 years, ”says Professor Peter Hartmann of the University of Western Australia, an expert in the field of lactation,“ After reaching this age, breast development stops, it becomes mature but remains “sleeping” for the time being. ”
During the menstrual cycle, breast cells are updated, which can make them more sensitive, painful, or swollen. 1
You probably noticed that at the beginning of the cycle, the chest is somewhat lumpy to the touch. During this period, preparation for a possible pregnancy occurs. If pregnancy does not occur, a new cycle of falling and rising hormone levels begins.
Internal breast changes during pregnancy
When conception occurs, the cycle is interrupted. From the end of the first month of pregnancy, the breast begins to gradually turn into an organ that produces milk.
At this time, the number and branching of the milk ducts increase and an extremely complex feeding system is formed. At the same time, cells called lactocytes, which produce milk, begin to develop in the chest. The amount of blood flowing to the breast doubles during pregnancy. That is why veins sometimes shine through the skin.
“After the birth of the placenta, the level of progesterone begins to fall and the lactation process starts”
“When pregnancy occurs, the breasts literally turn on,” says Professor Hartmann, “After conception, growth of the secretory tissue of the breast begins. Clusters are located in the chest, similar to tubercles of the glands, and when pregnancy occurs, these tubercles begin to grow and form ducts and tiny sacs, the so-called alveoli, in which milk will be stored. ”
All these processes occurring in the chest can cause feelings of heaviness, soreness and swelling, which relate to the early signs of pregnancy. Read more in the article on how the breast changes during pregnancy.
Lactating breast structure
Believe it or not, scientists have only recently established how a complex system of ducts located in the chest works.
Until the beginning of our century, most medical knowledge about milk production was based on experiments conducted by the English surgeon, Sir Astley Cooper, in 1840.4 He concluded that milk is stored in the ducts and exits through openings in the nipple, which number from 15 up to 20.
Incredibly, research on this subject continued only in 2005. Professor Hartmann’s colleague, Dr. Donna Geddes, together with a group of scientists with the support of Medela, discovered that the breasts function very differently.5 The ducts are really small tubes with a diameter of only a few millimeters, but they serve to transport milk and not to store . Milk is produced and stored in the alveoli. These sacs are connected to the ducts using even smaller tubes called tubules.
Milk remains in these bags until the hormone oxytocin is formed in the body, which happens when the baby begins to suckle. The alveoli are surrounded by muscle cells that contract under the influence of oxytocin, and these contractions move milk along the ducts to the nipple. This process is called the reflux of milk. Sometimes it can be felt like a tingling or slight movement that occurs in the chest when you begin to feed the baby, but some women do not feel it at all.
Dr. Geddes and colleagues also found that there are fewer holes in the nipples than previously thought: usually there are about nine, and sometimes only four. The ducts have to expand by almost 68% to accommodate the entire volume of milk flowing rapidly to these several outlets.