Our study is potentially limited by the use of maternal recall for breastfeeding outcomes and obstetrical events. Breastfeeding initiation was self-reported up to 10 years after the event and could be subject to recall bias, especially among women who breastfed for a short duration [24]. The generalizability of our results may be limited by the relatively high educational attainment and older age of our study participants, as well as by the exclusion of certain obstetrical conditions, such as prematurity, fetal anomalies, and multiple gestation. In addition, the study population was limited to women that could be contacted 5 to 10 years after birth, indicating that they had a stable residence. These factors did impact participant selection but do not imply selection bias, or a biased estimate of the association between maternal characteristics and breastfeeding practices.