Female Breast Development

Breast development in females is separated into five stages. While the first stage of breast development is prior to puberty, when the chest is flat and only the tips of the nipples are raised, a female’s breasts actually begin to “grow” at the onset of puberty when hormones are released by the pituitary gland.  Estrogen is believed to be the main hormone responsible for breast development.

The second stage typically begins in the years prior to adolescence. It is characterized by a small amount of swelling, or budding, as the nipple begins to develop and milk ducts form underneath. The darker area surrounding the nipple, called the areola, darkens and expands in size. Fat accumulates in breast tissue and milk ducts develop in the third stage, both contributing to additional volume. It is common for females to experience a certain amount of tenderness or discomfort in the breasts. There may also be itchiness as the skin in the area stretches.

The fourth stage is indicated by the maturation of the nipple and areola, which rise to form a small mound. This mound smoothens out in the final stage of breast development at eighteen years old or so; however some believe that the final stage is only achieved with pregnancy and lactation. In any case, at this time the entire breast assumes a “womanly” contour, rounding out with only the nipple remaining raised. The milk duct system is fully formed. It is typically recommended that maturation of the breast is completed before undergoing breast augmentation or mastopexy/breast lift.

A woman’s full breast size is achieved by the end of the final stage. However, menstrual cycles and increased estrogen levels can contribute to further growth. And since the breasts are mainly comprised of fat (adipose tissue), weight gain can also contribute to volume. It is common that the breasts lose volume with weight loss, the completion of menstrual cycles and lactation, as well as the normalization of estrogen levels. As a result, the breasts will return to the same size they were beforehand.

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More information about Female Breast Development.

About Breast Anatomy.

About Asymmetrical Breasts.