Progestin-related breast volume changes in a woman with complete androgen insensitivity syndrome (CAIS).

There is limited reports available on the effects of progesterone on breast development and volume. 3D imaging provides an easy-to-use method to quantify breast volume. The patient in our case description clearly showed that cyclic progesterone use might induce substantial cyclic changes in breast volume. In women with complete androgen insensitivity syndrome (CAIS), monotherapy with estrogen or continuous supplementation of progesterone might be preferable over cyclic progesterone use.