Breast augmentation
The modern prosthetic breast was invented in 1961, by the American plastic surgeons Thomas Cronin and Frank Gerow, and manufactured by the Dow Corning Corporation; in due course, the first augmentation mammoplasty was performed in 1962. There are five generations of medical device technology for the breast-implant models filled with silicone gel; each generation of breast prosthesis is defined by common model-manufacturing techniques.
Sex reassignment surgery (male-to-female)
Breast augmentation is the enlargement of the breasts. Some trans women choose to undergo this procedure if hormone therapy does not yield satisfactory results. Usually, typical growth for trans women is one to two cup sizes below closely related females such as the mother or sisters. Estrogen is responsible for fat distribution to the breasts, hips and buttocks, while progesterone is responsible for developing the actual milk glands. Progesterone also rounds out the breast to an adult Tanner stage-5 shape and matures and darkens the areola.