Thelarche

Beginning of development of the breasts in the female

Thelarche, also known as breast budding, is the onset of secondary breast development, often representing the beginning of pubertal development. It is the stage at which male and female breasts differentiate due to variance in hormone levels; however, some males have a condition in which they develop breasts, termed gynecomastia. Thelarche typically occurs between the ages of 8 and 13 years with significant variation between individuals. However, the initial growth of breast tissue occurs during fetal development.

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