The Swedish version of the BSES-SF has good reliability, validity, and agreement with mothers' plans regarding breastfeeding continuation and exclusivity.

Self-efficacy was an important predictor of the length of breastfeeding in mothers of late preterm infants, and the BSES-SF can be used to detect low self-efficacy that could lead to early breastfeeding cessation.

The aim of this study was to psychometrically test the Adaptation to the Late Preterm Infant when Breastfeeding Scale (ALPIBS) and also to test how a mother's self-efficacy predicts adaptation to a late preterm infant when breastfeeding. This study had a longitudinal and prospective design, and data collection was consecutive. Mothers (n = 105) with infants born between 34 0/7 and 36 6/7 weeks were recruited from a neonatal intensive care unit or a maternity unit. The ALPIBS was developed using exploratory factor analysis, and the association between breastfeeding self-efficacy and ALPIBS score was examined using linear regression analysis. The Breastfeeding Self-Efficacy Scale–Short Form instrument was used to measure self-efficacy in breastfeeding. A higher degree of self-efficacy was significantly associated with a higher degree of adaptation to the late preterm infant's breastfeeding behavior (P < .001). We identified 4 separate underlying factors measured by 11 items in the ALPIBS: (A) breastfeeding is a stressful event; (B) the infant should breastfeed as often as he or she wants; (C) a mother has to breastfeed to be a good mother; and (D) it is important to ensure control over the infant's feeding behavior. There is a link between self-efficacy and ALPIBS score, and self-efficacy is a modifiable factor that influences breastfeeding.