Breast development is a process that provides women with the tissue and structures necessary for the eventual production of breast milk to sustain life. Generally, development starts early in life, with outward signs of changes that occur during puberty. In some cases, these changes manifest during adolescence, while in other cases, begin substantially earlier.
The initial structure of the chest, called breast edge, begins to form during fetal development, according to the Medical Center Ohio State University . In addition to the externally visible nipples, girls are born with rudimentary milk ducts. When puberty begins, the ovaries start to secrete estrogen, which in turn causes breast enlargement through the accumulation of fat in the connective tissue of the breasts. While rudimentary duct system begins to grow, with secreting glands which are formed at the ends of the milk line (see Reference 1).
In the first visible stage of prepubertal breast development, the tips of the nipples will rise from the surrounding breast tissue, according to the Ohio State University . In the next stage of development, the tissue around the nipples blossom and dark areas of the skin around the nipples (called areola) will start to increase. In the third stage, the development of glandular tissue lead to further enlargement of the breasts. In the fourth stage, the nipples and the areolas are usually elevated above the surrounding breast tissue. In the fifth and final stage, the breast will look rounded and halos decrease in height (see References 1).
While some girls do not experience puberty and breast enlargement through adolescence, other girls may experience these changes in the early age of seven or eight years, according to the Health Center for Young Women’s Hospital Boston Children. Factors that may influence the onset of breast development at puberty are genetics, history of disease, nutrient intake, body weight and stress levels and exercise. In addition, girls may experience a relative delay in puberty and breast development if they participate in strenuous sports, such as athletics and gymnastics (see References 2).
Each girl undergoes breast development at an individual pace, says the Children’s Hospital Boston. In some cases, differences in rates may foster insecurity or uncertainty in girls. If this is the case, you can encourage them to discuss their feelings with you or another trusted adult. If girls do not show signs of development by the age of 13, a physician should be consulted for guidance and advice (see References 2).
Male Breast Development
Approximately 70 percent of children experience temporary breast development during adolescence as a result of hormonal imbalance or other causes, according to the Hospital MassGeneral for Children. Usually, this development is manifested as a bundle within a firm and tender inch (2.5 cm) in diameter. The temporary extension usually lasts less than two years, and while your child’s doctor note this development, it is likely that the treatment is unnecessary. If male breast development occurs after adolescence, the doctor may order other diagnostic tests (see References 3).