Nipple (papilla) development in girls: III. The effects of pregnancy.

Previous cross-sectional and longitudinal studies of girls have documented that they have a significant growth in nipple size during Tanner stages pubic hair (PH)4 and PH5 or breast (B)4 and B5. This study assesses whether there is any effect of pregnancy on nipple development in adolescent girls. Thirty-three pregnant girls were compared to a previously reported group of 390 girls who were not pregnant. Of the 33 girls, ten were followed longitudinally for a period of nine to 79 months, during which time they became pregnant. In each girl, nipple diameter was measured and the Tanner stage assessed. A markedly significant increment in nipple size was noted in the girls who were pregnant (pregnancy nipple size 12.6 mm vs. PH5 9.7 mm and B5 9.9 mm). Comparison of ten girls prior to and during pregnancy revealed a significant increment as well (10.2 mm vs. 12.8 mm, respectively). Pregnancy provides a further stimulus for nipple development in girls beyond that which occurs during normal puberty.