Rohn R D
J Adolesc Health Care. 1982 Mar;2(3):217-20. doi: 10.1016/s0197-0070(82)80044-2.
The purpose of this study was do compare breast papilla (nipple) development to the established criteria of secondary sexual maturation. One hundred and sixty-eight girls (100 black and 68 white) ranging in age from 2-21 years had their papilla diameter measured and their Tanner stage assessed. Minimal nipple development occurred from stages PH1-PH3 (2.91-4.08 mm) and B1-B3 (2.75-3.96 mm) or premenstrually (3.61 mm). Significant growth occurred beyond stages PH3, B3 (PH4-7.22 mm, Ph5-9.36 mm, B4-7.74 mm, B5-9.47 mm) and near or after menarche (7.82 mm for girls 0-2 years post-menarche, 9.23 mm for girls 2-4 years post-menarche and 9.65 mm for girls more than four years after menarche). A more objective definition for breast stages B4 and B5, based on nipple diameter, may now be feasible, thus enhancing the precision with which physiologic events occurring toward the close of puberty can be studied.