The development of breasts in human beings happens years before it is used for giving feed to a newborn. The development of female busts happens at many stages. The first stage of development starts before birth and later it happens after puberty. Women may have further see the changes in shape and size of busts, during pregnancy and after childbirth nursing.
Starting stage of development: The initial phase of bust development starts with the thickening of the chest area, which is also called the mammary ridge or the milk line. The female baby has a nipple and the initial stage of milk duct formation.
The change in structure and shape of busts can be seen throughout the life. The lobes and the branches of the tissues develop first and then the mammary glands are formed, which contains fifteen to twenty four lobes. The mammary glands formation is supported by the secretion of hormones during puberty. After the development phase, the shrinkage of mammary ducts starts, which happens around the age of thirty-five.
Changes in structure of breasts during adolescence: During adolescence, the busts development can be externally seen. The ovaries starts secreting the estrogen hormone and the fat deposits are formed in the connective tissues found inside the busts. Other changes in the body can be seen in a female body such as appearance of pubic hair and hair in the underarms. The girls reaching puberty starts the monthly cycles as the secretary glands are formed at the end of the milk ducts.
The rate of growth of busts varies from women to women. Sometimes, a girl has an early growth of busts but the final shape is formed after many years and sometimes, the growth is fast and it starts late. The complete growth of busts happens by the age of eighteen years although it can start by eleven or even before. Some girls can see changes in structure of busts in the age of nine and early growth is common in African – American ethnic group. But, early growth of busts does not indicate that the girl will have bigger busts in later age. The size of busts and growth pattern is mostly determined by hereditary factor.
Stage 1: Tip of nipple is raised (which is also called the preadolescent stage).
Stage 2: The nipple buds can be seen and the areola darkens and enlarges.
Stage 3: The size increases.
Stage 4: Areola and nipples rise to form the second mound above the first layer.
Stage 5: The growth is completed as the breasts become rounded and nipples are raised.
Most of the physicians believe that the breast is not developed fully until the woman gets pregnant and gives breastfeed. During pregnancy many changes in busts can be noticed along with the growth of fetus. Women may have darkening of areolas and swelling in breasts during pregnancy and certain changes in the structure of busts is also seen before the start of monthly cycle.