The endocrine system is comprised of glands that secrete hormones, chemical substances that travel in the bloodstream to target tissues, where they help to regulate body growth and direct the development and functioning of primary and secondary sexual structures including breasts.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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