More… well, very big

Hypertrophy of the breast (macromastia and gigantomastia) is a rare disease of the breast connective tissues; the indication is a breast weight increase that exceeds 600 grams (21 oz), which enlargement causes muscular discomfort and over-stretching of the skin envelope, leading to ulceration.^[1] Hypertrophy of the breast tissues might be caused by increased histologic sensitivity to the female hormonesprolactin, estrogen, and progesterone; or an abnormally elevated hormone(s) level in the blood, or both.^[2] Macromastia is the bilateral, benign progressive enlargement of the breasts; gigantomastia was first scientifically described in 1648.^[3]
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Well I know who have “IT” by nature … But who deliberately makes himself such a beauty I can not understand 

Hypertrophy of the breast can affect the breasts equally, but usually affects one breast more than the other, thereby causing asymmetry, when one breast is larger than the other. The condition can also individually affect the nipples and areola instead of or in addition to the entire breast. The effect can produce a minor size variation to an extremely large breast asymmetry. Breast hypertrophy is classified in one of five ways: as either pubertal (virginal hypertrophy), gestational (gravid macromastia), in adult women without any obvious cause, associated with penicillamine therapy, and associated with extreme obesity.^[1] The underlying cause of the rapidly growing breast connective tissue, resulting in gigantic proportions, is thought to be a heightened sensitivity to female hormones prolactin, estrogen and progesterone.
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