The endocrine system sends messages throughout the body via hormones, chemical messengers produced by glands within the body. The endocrine system is responsible for physical growth, energy balance and the development of sex organs, including the breasts.
Many hormones work in concert to influence initial breast development and to prepare the breast for lactation during and just after pregnancy. In this complex endocrine system, tiny, targeted amounts of hormone can exert big changes in the body.
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