Breast pain and swelling are generally not related to folic acid intake, as such pain and swelling are usually associated with breast hyperplasia, which is often related to endocrine disorders leading to increased levels of estrogen. The breast is a target organ for many endocrine glands, and its physiological activities are influenced by hormones secreted by the pituitary gland, ovaries, and adrenal cortex. The pituitary gland can directly affect the breast through prolactin. At the same time, estrogen and progesterone produced by the ovaries and adrenal cortex indirectly affect the breast. During pregnancy, breast cancer is influenced by estrogen and progesterone produced by the placenta. During pregnancy and lactation, the breast noticeably proliferates, with ductal elongation and alveolar secretion of milk. After breastfeeding, breast tissue returns to a relatively quiescent state.