Background: Nipple dimensions may be an important factor in breastfeeding (BF) initiation success. Objective: To establish standards of nipple/areola dimensions in early BF and to determine whether maternal age, gestational age (GA), parity, cup size, previous BF experience, and early (<2 hours) BF affect nipple dimensions (assessed on the second day of BF). Design/Methods: A total of 205 consecutive BF women were enrolled. They were all Caucasians, and had uncomplicated pregnancies, labors, and vertex vaginal deliveries. Measurements (immediately before and after BF) of nipple length and diameter and of prefeeding areolas were by sliding calipers. Results: In average, there were no significant differences between right (R) and left (L) side dimensions, except for post-BF nipple length, and post-BF horizontal nipple diameter (significantly higher on the L side). Both R and L nipple length correlated positively with maternal age, gravidity, parity, number of previously breastfed infants, and cumulative number of BF months. Early (<2 hours) first BF did not correlate with increased nipple length. Pre-BF nipple length correlated significantly with post-BF nipple length on both sides. There were significant differences between pre- and post- BF values in terms of nipple length (longer length post-BF), but not in terms of nipple diameter. In stepwise regression analysis, where pre-BF nipple length was the dependent variable, and parity (or maternal age, or previous BF), early first BF, and GA were independent variables, parity, maternal age, gravidity, or previous BF experience were positively and significantly associated with nipple length (p < 0.001). The correlation maternal age-nipple length remained significant in primigravida mothers. Conclusions: This study provided a set of standards for nipple and areola dimensions on day 2 of BF in Caucasian women. The only areola/nipple dimension significantly affected by BF is the nipple length. Increasing parity, maternal age, or previous BF experience is significantly associated with increased nipple length.
Keywords: breast dimensions; breast latching; breastfeeding; nipple length.