Factors Associated with Breastfeeding Intention among Late Adolescent Female Students

Introduction Breast milk contains essential nutrients, including proteins, carbohydrates, fats, vitamins, and minerals. Breastfeeding benefits both mothers and infants by enhancing the immune system and reducing respiratory and gastrointestinal infections. However, the breastfeeding rates among adolescent mothers worldwide and in Thailand remain low. As adolescents transition to adulthood, it is crucial to promote breastfeeding intention before pregnancy, particularly among late school-aged students in vocational education. Previous studies have shown that breastfeeding knowledge, attitudes toward breastfeeding, subjective norms, and perceived behavioral control are associated with breastfeeding intention. However. studies are limited in late adolescent female students in vocational education. Objective This research aimed to 1) study the intention to breastfeed and 2) investigate factors associated with breastfeeding intention, including breastfeeding knowledge, attitudes toward breastfeeding, subjective norms about breastfeeding, and perceived breastfeeding behavioral control among late adolescent female students in vocational education. Design A descriptive correlational design. This study utilized the Theory of Planned Behavior (TPB) by Ajzen, which explains that a person’s intention is related to their attitudes toward breastfeeding behavior, subjective norms about breastfeeding behavior, perceived behavioral control over breastfeeding, and breastfeeding knowledge, which is a background factor associated with breastfeeding intention. Methodology The participants included late adolescent students aged 17-19 years who were studying in the third year of vocational program and the first and second year of higher vocational program under the Vocational Education Commission in Bangkok from May to June 2024. The sample size was calculated using the G*Power program. The effect size was set at 0.184, the power of the test was .95 and the level of significance was .05, obtaining 311 participants. The researchers added 10% to account for data incompletion, resulting in a total of 342 participants. The research instruments consisted of 6 parts, including 1) a personnel information questionnaire, 2) breastfeeding knowledge questionnaire, 3) attitudes toward breastfeeding questionnaire, 4) subjective norm about breastfeeding questionnaire, 5) perceived behavioral control questionnaire, and 6) breastfeeding intention questionnaire. In this study, the content validity indices of the breastfeeding knowledge questionnaire, attitudes toward breastfeeding questionnaire, subjective norms about breastfeeding questionnaire, perceived breastfeeding behavioral control questionnaire, and breastfeeding intention questionnaire were .96, 1, .80, .96, and 1 respectively. The reliability, Kuder-Richardson 20 for the breastfeeding knowledge questionnaire was .72. The attitudes toward breastfeeding questionnaire, subjective norms about breastfeeding questionnaire, and perceived breastfeeding behavioral control questionnaire had Cronbach’s alpha coefficient of .74, .86, and .93, respectively. Data were collected using self administration, from May to June 2024. Data were then analyzed using descriptive statistics and Pearson’s product moment correlation coefficient. Results Among 342, 332 participants met the criteria in this study. The average age of the participants was 18.27 years old (SD = 0.69). Most of them lived with their parents (78.31%). The family income of 10,001-20,000 baht/month was the highest frequency (34.6%). The results showed that breastfeeding intention was high. It was significantly associated with breastfeeding knowledge (r = .172, p = .002), attitudes toward breastfeeding (r = .190, p < .001), subjective norm about breastfeeding (r = .389, p < .001), and perceived breastfeeding behavioral control (r = .429, p < .001). Recommendation This study provides preliminary data for nurses to plan the promotion of breastfeeding knowledge, attitudes toward breastfeeding, subjective norms about breastfeeding, and perceived breastfeeding behavioral control. These efforts will contribute to increasing breastfeeding rates in the future.