Breastfeeding is the feeding of a child with breast milk, either directly from the breast or by expression. Breastfeeding offers tremendous benefits to both the infant and mother. Individuals choose tasks they feel are within the boundaries of ability. The choice to engage in breastfeeding may be related to the level of self-efficacy a woman has to complete the task. Theoretical constructs have been operationalized to measure perceived self-efficacy for breastfeeding in pregnant populations; however, a guideline based, self-efficacy theory driven, valid, and reliable instrument is lacking. The purposes of this study were to create, test, and validate a new scale to measure prenatal breastfeeding self-efficacy, test the reliability of the scale, determine the correlation between prenatal breastfeeding self-efficacy and breastfeeding intention, and assess the differences in prenatal breastfeeding self-efficacy by the sociodemographic factors. One-hundred and twenty-four pregnant women, 18 years or older, participated in this cross-sectional study. All participants completed the survey and any interested participant took a second retest reliability survey home to complete and mail back to the researcher. Confirmatory factor analysis did not confirm the proposed model; therefore, an exploratory factor analysis was conducted to examine the construct validity using maximum likelihood factor analysis with varimax rotation. This revealed a valid (α=.980) and reliable (r=0.920) four factor questionnaire for total prenatal breastfeeding self-efficacy – The Prenatal Rating of Efficacy in Preparation to Breastfeed (PREP to BF) Scale. Total PREP to BF score was significantly correlated to breastfeeding intention (r=.615; P<.001). Women who had at least some college education (P=.003), were currently married (P=.027), had breastfed previously (P=.035), and planned to deliver vaginally (P=.043) had significantly greater PREP to BF scores than their counterparts. Measuring the level of breastfeeding self-efficacy at the prenatal stage could alert prenatal women and health professionals to particular individual skill sets needed to successfully initiate breastfeeding after birth. A strong understanding of which pregnant women may or may not be at risk for non-initiation of breastfeeding may help healthcare professionals create and provide the most appropriate support to their patients.