Effectiveness of the Enjoy‐Breastfeeding Mom App on Breastfeeding Knowledge, Attitudes, Self‐Efficacy, and Infant Responsiveness Among Thai Adolescent Mothers: A Three‐Arm Randomised Controlled Trial

ABSTRACT

Adolescent mothers experience persistent barriers to optimal breastfeeding, while evidence on the effectiveness of digital breastfeeding interventions tailored to this population remains limited. This three‐arm, multicentre randomised controlled trial evaluated the effectiveness of the Enjoy‐Breastfeeding Mom smartphone application on breastfeeding‐related knowledge, attitudes, breastfeeding self‐efficacy and maternal knowledge of infant cues and responsiveness among Thai adolescent mothers. A total of 150 primigravida adolescent mothers aged 15–19 years were recruited from four tertiary hospitals across Thailand and randomly allocated to (1) antenatal‐to‐postpartum application use, (2) postpartum‐only application use or (3) usual nursing care (50 per group). Outcomes were assessed at baseline (30–34 weeks' gestation), postpartum day 3, and 30 days postpartum. Data were analysed using repeated‐measures analysis of variance following the intention‐to‐treat principle, in accordance with the CONSORT Statement for non‐pharmacological randomised clinical trials. Breastfeeding knowledge and attitudes were higher in both intervention groups than in usual care, with larger effects observed in the postpartum application group for knowledge (mean difference = 1.87, 95% CI 1.13–2.61) and in the antenatal application group for attitudes (mean difference = 7.95, 95% CI 6.52–9.36). Breastfeeding self‐efficacy increased over time across all groups, with no clear between‐group differences. Knowledge of infant cues and responsiveness was modestly higher in the intervention groups than in usual care (antenatal: mean difference = 0.70, 95% CI 0.21–1.19; postpartum: mean difference = 0.62, 95% CI 0.13–1.11). The Enjoy‐Breastfeeding Mom application effectively improved breastfeeding knowledge and attitudes among Thai adolescent mothers. Adolescent‐tailored digital interventions may enhance breastfeeding education and maternal learning when integrated with routine nursing care.

Trial Registration:Thai Clinical Trials Registry (TCTR20240918007). Registered 18/09/2024.

Summary

• This study provides randomised controlled trial evidence on the effectiveness of a smartphone‐based breastfeeding intervention tailored for adolescent mothers, an underrepresented population in digital health research.

• The findings suggest that the timing of digital breastfeeding support influences different outcomes, with antenatal‐to‐postpartum use favouring breastfeeding attitudes and postpartum‐only use favouring knowledge acquisition.

• The study shows that nurse‐supported mobile applications can enhance breastfeeding education and learning of infant cues, offering a scalable approach to reduce inequities in breastfeeding support across diverse healthcare settings.

1. Introduction

Promoting optimal breastfeeding is central to achieving the United Nations Sustainable Development Goals (SDGs) to reduce preventable child mortality, promote lifelong health, and address health inequities across populations (UNICEF 2016). Breastfeeding contributes substantially to supporting maternal health and reducing health inequities across the life course (Black et al. 2008; Hanson et al. 2012; Jones et al. 2003). Strengthening breastfeeding practices is increasingly recognised as integral to advancing global goals.

Breastfeeding outcomes remain suboptimal in many contexts, particularly among socially and developmentally vulnerable populations. Adolescent mothers experience unique challenges related to limited breastfeeding knowledge, lower self‐efficacy and difficulties in recognising and responding to infant cues (Nuampa et al. 2019, 2024; Sudphet et al. 2025). In Thailand, national surveillance data indicate that, in 2022, the prevalence of exclusive breastfeeding at 6 months was 28.6%, remaining substantially below the global target (National Statistical Office of Thailand 2016, 2020). These highlight the need for interventions that can strengthen optimal breastfeeding outcomes, particularly among adolescent mothers.

Breastfeeding among adolescent mothers is often challenging, as it occurs alongside ongoing psychological, cognitive, and physical development characteristic of adolescence (Mossman et al. 2008). Prior studies have identified factors contributing to early breastfeeding cessation among adolescent mothers, including stigma and embarrassment associated with breastfeeding, concerns related to bodily exposure, negative attitudes towards breastfeeding, limited self‐efficacy, insufficient knowledge and skills and inadequate social and professional support (Monteiro et al. 2014; Tucker et al. 2011). Given these distinct developmental and contextual challenges, breastfeeding support strategies tailored specifically to adolescent mothers are essential (Renfrew et al. 2012).

Evidence from Thailand indicates that adolescent mothers frequently experience early breastfeeding difficulties, contributing to early supplementation and premature weaning (Nuampa et al. 2022). Low self‐efficacy, limited knowledge and inadequate support are key factors associated with suboptimal outcomes (Nuampa et al. 2018). Breastfeeding practices are further shaped by psychosocial and family contexts, including limited autonomy and decision‐making power. Consequently, adolescent mothers often rely on online sources for information due to embarrassment, fear of judgement or limited access to continuous professional support (Sudphet et al. 2025). Existing evidence suggests that breastfeeding interventions for adolescent mothers are most effective when educational input is combined with personalised counselling. Systematic reviews and empirical studies show that such approaches can improve breastfeeding initiation, increase exclusive breastfeeding in the early postpartum period and support longer breastfeeding duration (Sipsma et al. 2015; De Oliveira et al. 2014; Yılmaz et al. 2016).

Maternal health information‐seeking has increasingly shifted towards digital platforms, with growing reliance on online resources for breastfeeding support (Celik 2017). Evidence suggests that electronically delivered interventions can extend the reach and continuity of support, particularly when incorporating interactive communication and counselling features (Pate 2009; Jiang et al. 2014; Tang et al. 2019; Wang et al. 2018). Although mobile applications are widely used for breastfeeding support, most existing apps target adult mothers and vary in scope and quality. These applications commonly provide breastfeeding information, tracking tools and peer or professional support (Balaam et al. 2015; Demirci and Bogen 2017; White et al. 2016; Doan et al. 2020; Meedya et al. 2021). However, few are designed to address the developmental and contextual needs of adolescent mothers, and concerns remain regarding information quality and limited evidence of effectiveness (Diniz et al. 2019).

In Thailand, smartphone use among adolescents is widespread, providing a feasible and accessible platform for delivering breastfeeding support. Prior formative studies suggest that digital interventions may enhance breastfeeding‐related learning and maternal confidence (Nuampa et al. 2024). However, rigorous evaluation of their effectiveness remains limited, particularly in relation to knowledge, attitudes, self‐efficacy and infant responsiveness. This study, therefore, aimed to evaluate the effectiveness of the Enjoy‐Breastfeeding Mom smartphone application on these outcomes among Thai adolescent mothers using a three‐arm randomised controlled trial.

2. Methods

2.1. Research Design

This study was conducted in Thailand as a three‐armed, multi‐centre, randomised controlled trial comparing three conditions: IG1 (apply APP at antenatal period), IG2 (apply APP at postpartum period) and CG (standard‐of‐care). The randomised controlled trial report adhered to the Consolidated Standards of Reporting Trials (CONSORT) guidelines for randomised trials of non‐ pharmacological treatments (Boutron et al. 2017) (File S1). The study protocol was registered at Thai Clinical Trials Registry: TCTR (September 2024) with reference number TCTR20240918007.

2.2. Study Setting and Population

This multicentre randomised controlled trial was conducted in four tertiary hospitals representing Thailand's four major regions (North, Central, Northeast and South). Participants were assessed for eligibility and recruited consecutively from antenatal clinics at the participating sites.

The eligibility criteria of this study were predefined to minimise clinical confounding. Adolescent pregnant women were eligible if they were 15–19 years old at the expected date of delivery, primigravida and between 30 and 34 weeks' gestation at enrolment. Only those with an uncomplicated pregnancy were included. Participants were also required to own and be able to use a smartphone to access the intervention. Participants were excluded if they failed to complete study questionnaires or developed pregnancy or postpartum complications that could affect breastfeeding outcomes, including gestational diabetes mellitus, hypertensive disorders of pregnancy, preterm birth (< 37 weeks' gestation), sexually transmitted infections or substance use. Women with a diagnosed mental health condition during pregnancy or postpartum, and mother–infant dyads separated for more than 24 h postpartum, were also excluded. Participants allocated to the intervention groups who did not access the application within 1 week or did not complete the assigned learning modules were classified as having intervention non‐adherence.

2.3. Sample Size Calculation and Sampling

Sample size was calculated using G*Power 3.1.9.4, based on an effect size f of 0.33 for exclusive breastfeeding at 1 month postpartum reported in Thai adolescent mothers (Khunpong et al. 2024). With a power of 0.95 and a two‐sided alpha of 0.05, the required sample size was 147 participants. A total of 150 participants were recruited, with 50 participants per group, to allow for balanced allocation across the three study groups.

Participant recruitment was undertaken between November 2024 and June 2025. Eligible pregnant adolescent women attending routine antenatal clinics were recruited consecutively at each study site. To ensure balanced recruitment across regions, the target sample size per group was distributed as follows: hospitals in the Northern and Central regions recruited 12 participants per group, whereas hospitals in the Northeastern and Southern regions recruited 13 participants per group, resulting in an equal overall allocation of 50 participants per group across the four sites.

2.4. Randomisation

After eligibility screening and baseline assessment, participants were allocated to one of three groups: (1) antenatal‐to‐postpartum application use, (2) postpartum‐only application use or (3) usual nursing care. A restricted randomisation procedure with a 1:1:1 allocation ratio was used to ensure balanced group sizes across study sites. A pre‐specified allocation sequence was generated using a random number table and organised into repeating cycles. At each hospital, eligible participants were recruited consecutively and assigned sequentially according to the allocation sequence, with up to six participants enrolled per day. When fewer than six participants were recruited, allocation continued according to the same sequence. Recruitment and allocation proceeded until the target sample size at each site was achieved.

2.5. Blinding Design

Blinding of participants and intervention providers was not feasible due to the nature of the smartphone‐based intervention. However, outcome assessors and data analysts were blinded to group allocation throughout outcome assessment and statistical analysis to minimise potential bias. Allocation concealment was maintained during recruitment, as antenatal clinic nurses were unaware of the randomisation sequence and upcoming group assignments.

2.6. Intervention

The “Enjoy‐Breastfeeding Mom smartphone application” was developed to support breastfeeding practices and maternal learning among Thai adolescent pregnant women and adolescent mothers. The application delivers stage‐specific content from pregnancy to 6 months postpartum, structured as a “Breastfeeding Journey Map” that aligns breastfeeding knowledge and caregiving skills with maternal and infant needs over time. Content development was informed by a review of the literature on breastfeeding among adolescent mothers and by empirical studies examining breastfeeding experiences and related factors in this population (Nuampa et al. 2018, 2019, 2024). The application integrates interactive learning materials and professional support to facilitate breastfeeding‐related knowledge acquisition and learning of infant cues and responsiveness (Table 1).

Table 1.

Overview of the “Enjoy‐Breastfeeding Mom” smartphone application.

Component	Timing/Period	Description
Programme structure	Pregnancy to 6 months postpartum	Stage‐based breastfeeding support organised as a Breastfeeding Journey Map
Stage 1	Pregnancy (1st–2nd trimester)	Breast and nipple changes; breast care; benefits of breastfeeding; rationale for exclusive breastfeeding; risks of early supplementation
Stage 2	Pregnancy (3rd trimester)	Physiology of milk production and milk flow; principles of effective feeding
Stage 3	Birth period	Vaginal birth and its benefits; coping with labour pain; immediate skin‐to‐skin contact
Stage 4	First week postpartum	Positioning and latch; recognising effective sucking; infant cues and responsiveness; common early breastfeeding problems
Stage 5	1 week–1 month postpartum	Managing breastfeeding, nutrition, and rest; common breastfeeding challenges; infant play (0–1 month)
Stage 6	1–3 months postpartum	Milk expression and pumping; milk storage; breastfeeding and return to school/work; infant play (1–2 months)
Stage 7	3–6 months postpartum	Maintaining milk supply; addressing conflicting beliefs about exclusive breastfeeding; common breastfeeding challenges; infant play (3–6 months)
Interactive learning	All stages	Short videos, animated illustrations, quizzes and interactive activities
Gamification	All stages	Point accumulation displayed on a personalised dashboard; points used for virtual baby‐room customisation
Self‐monitoring	Antenatal and postpartum	Daily diary for recording breastfeeding‐related experiences
Mental health screening	Postpartum	In‐app screening for depressive symptoms
Peer interaction	All stages	Group discussion board for peer exchange
Professional consultation	Antenatal and postpartum	In‐app consultation with trained research nurses from participating hospitals

2.6.1. Measurement

Five instruments were used for data collection to assess participant characteristics and primary study outcomes, including breastfeeding‐related knowledge, attitudes, self‐efficacy and knowledge of infant cues and responsiveness.

• 1.Demographic, Pregnancy, and Breastfeeding Questionnaire: This self‐administered questionnaire comprised 17 closed‐ended items covering demographic characteristics, pregnancy‐related information and breastfeeding‐related information.
• 2.Breastfeeding Knowledge Questionnaire: Breastfeeding knowledge was assessed using an adapted version of the questionnaire developed by Laanterä et al. (2010). Two open‐ended items were removed, resulting in a 20‐item true/false questionnaire (score range 0–20; higher scores indicate greater knowledge). Of the 20 items, six statements were correctly keyed (Items 5, 6, 7, 11, 13 and 18). Content validity was confirmed by expert review (CVI = 0.98). Baseline internal consistency was acceptable (KR‐20 = 0.84).
• 3.Breastfeeding Attitude Questionnaire: Attitudes towards breastfeeding were measured using a modified Thai version of the Iowa Infant Feeding Attitude Scale (IIFAS) (Mora et al. 1999). The Thai version contains 17 items, rated on a 5‐point Likert scale, with six negatively worded items adapted for cultural appropriateness (Items 1, 2, 6, 7, 8 and 17). Total scores range from 17 to 85, with higher scores reflecting more positive attitudes towards breastfeeding. Negatively worded items were reverse‐scored prior to analysis. Content validity was confirmed by expert review (CVI = 1.00). Baseline internal consistency was good (Cronbach's α = 0.88).
• 4.Breastfeeding Self‐Efficacy Questionnaire: Breastfeeding self‐efficacy was assessed using the Thai version of the Breastfeeding Self‐Efficacy Scale–Short Form (BSES‐SF) (Dennis 2003) (14 items; 5‐point Likert scale; score range 14–70). Content validity was confirmed by expert review (CVI = 1.00). Baseline internal consistency was excellent (Cronbach's α = 0.93).
• 5.Infant Cues and Responsiveness Knowledge Questionnaire: Knowledge of infant cues and responsiveness was assessed using a 12‐item, image‐based questionnaire developed by the researchers based on Barnard's caregiving model (1994). Correct responses were scored as 1, and incorrect or uncertain responses as 0 (score range 0–12). Of the 12 items, three items were incorrectly keyed (Items 7, 8 and 12). Content validity was established through expert review (CVI = 0.98). Baseline internal consistency was acceptable (KR‐20 = 0.78).

2.6.2. Data Collection

Data collection was conducted at three time points: baseline (30–34 weeks' gestation), postpartum day 3 and 30 days postpartum (Table 2). All participants completed baseline assessments prior to randomisation. The timing of application access differed between the two intervention groups, with the antenatal‐to‐postpartum group receiving access after baseline assessment and the postpartum‐only group receiving access after the first post‐test. The control group received routine care throughout the study period. Outcome assessments were identical across groups at each time point.

Table 2.

Timeline of data collection and intervention delivery.

Study period	Intervention group 1 (antenatal–postpartum app)	Intervention group 2 (postpartum app)	Control group
30–34 weeks' gestation	Pretest: Demographic, pregnancy and breastfeeding information; breastfeeding knowledge; breastfeeding attitude; breastfeeding self‐efficacy; infant cues and responsiveness knowledge	Pretest: Demographic, pregnancy and breastfeeding information; breastfeeding knowledge; breastfeeding attitude; breastfeeding self‐efficacy; infant cues and responsiveness knowledge	Pretest: Demographic, pregnancy and breastfeeding information; breastfeeding knowledge; breastfeeding attitude; breastfeeding self‐efficacy; infant cues and responsiveness knowledge
After the pretest (antenatal)	Access to the Enjoy‐Breastfeeding Mom application and standardised instructions for use	Routine care	Routine care
Postpartum day 3	Post‐test 1: Breastfeeding knowledge; breastfeeding attitude; breastfeeding self‐efficacy; infant cues and responsiveness knowledge	Post‐test 1: Breastfeeding knowledge; breastfeeding attitude; breastfeeding self‐efficacy; infant cues and responsiveness knowledge	Post‐test 1: Breastfeeding knowledge; breastfeeding attitude; breastfeeding self‐efficacy; infant cues and responsiveness knowledge
After post‐test 1	Continued application use	Access to the Enjoy‐Breastfeeding Mom application and standardised instructions for use	Routine care
Postpartum day 30	Post‐test 2 (online): Breastfeeding knowledge; breastfeeding attitude; breastfeeding self‐efficacy; infant cues and responsiveness knowledge	Post‐test 2 (online): Breastfeeding knowledge; breastfeeding attitude; breastfeeding self‐efficacy; infant cues and responsiveness knowledge	Post‐test 2 (online): Breastfeeding knowledge; breastfeeding attitude; breastfeeding self‐efficacy; infant cues and responsiveness knowledge

2.7. Outcome Assessment

Study outcomes were assessed at three predefined time points: baseline (30–34 weeks' gestation), postpartum day 3 and 30 days postpartum. The primary outcomes were breastfeeding‐related knowledge, breastfeeding attitudes, breastfeeding self‐efficacy and maternal knowledge of infant cues and responsiveness. These outcomes were measured using validated questionnaires as described in the Measures section. Baseline assessments were completed prior to randomisation. Post‐intervention assessments were conducted at postpartum day 3 (post‐test 1) and at 30 days postpartum (post‐test 2) using identical outcome measures across all study groups. Breastfeeding practices and infant feeding information at 30 days postpartum were collected via telephone follow‐up. Outcome data were collected by trained research staff who were blinded to group allocation, and all assessments followed standardised procedures to ensure consistency across study sites.

2.8. Data Analysis

Data were analysed using SPSS version 20 (IBM Corp., Armonk, NY, USA). Descriptive statistics were used to summarise participant characteristics and study variables. Continuous variables were presented as means and standard deviations, while categorical variables were reported as frequencies and percentages. Baseline characteristics across the three study groups were described to allow assessment of group comparability.

Primary analyses were conducted according to the intention‐to‐treat principle, including all randomised participants in their originally allocated groups regardless of application use or completion of learning modules. Differences in breastfeeding‐related outcomes across the three study groups over time were examined using repeated‐measures analysis of variance. Post hoc comparisons were performed as appropriate to explore between‐group differences. When the assumption of sphericity was violated, the Greenhouse–Geisser correction was applied. Statistical significance was set at p < 0.05 (two‐tailed).

2.9. Ethical Statement

This study was conducted in accordance with internationally accepted ethical principles for research involving human participants. The major project, “Development of a Smartphone Application for Promoting Breastfeeding and Learning of Infant Responsiveness for Thai Teenage Pregnant Women,” obtained ethical approval from all participating institutions prior to the commencement of data collection. Ethical clearance was granted by the Mahidol University Multi‐faculty Cooperative IRB Review (MU‐MOU CoA No. IRB‐NS2022/650.1601), the Ethic Committee for Research in Human Subject, Hatyai Hospital (Protocol Number: HYH EC 077‐67‐02), the Ethic Committee for Research in Human Subject, Maesod Hospital, Ministry of Public Health (COA No.24; MSHP REC No.24/2567) and the Maharat Nakhon Ratchasima Hospital Institutional Review Board (CoA No. 038/2025). Written informed consent was obtained prior to enrolment and before any study procedures were undertaken. Participants were informed of their right to withdraw at any time without consequences. To ensure confidentiality, consent forms were stored separately from study data, and each participant was assigned a unique identification code. All data were anonymised prior to analysis.

3. Results

3.1. Participant Characteristics

A total of 150 adolescent pregnant women were enrolled and equally allocated across the three study groups (n = 50 per group). Baseline demographic, obstetric and breastfeeding‐related characteristics are presented in Tables 3 and 4.

Table 3.

Demographic, obstetric and baseline breastfeeding‐related characteristics across study groups (n = 150).

Characteristic	Antenatal app (Tx1) (n = 50)	Postpartum app (Tx2) (n = 50)	Usual care (C) (n = 50)
Age (years)	17.40 (1.32)	17.62 (1.27)	17.22 (1.35)
Gestational age at first ANC visit (weeks)	14.62 (7.36)	16.40 (9.19)	14.5 (7.73)
Planned maternity leave (months)	3.22 (1.74)	3.26 (1.54)	3.18 (1.59)
Intended duration of breastfeeding (months)	3.44 (0.70)	3.34 (0.96)	3.30 (0.93)
Breastfeeding knowledge	11.64 (2.42)	11.82 (2.44)	11.02 (1.36)
Breastfeeding self‐efficacy	48.12 (10.63)	48.68 (9.69)	46.14 (7.02)
Attitude toward breastfeeding	57.04 (3.35)	56.34 (3.26)	55.82 (3.33)
Knowledge of infant cues and responsiveness	9.88 (1.42)	9.86 (1.80)	9.52 (2.11)

Note: One‐way ANOVA was used for continuous variables; mean (SD).

Table 4.

Demographic, obstetric and breastfeeding support factors across study groups (n = 150).

Characteristic	Total N (%)	Antenatal app (Tx1) (n = 50)	Postpartum app (Tx2) (n = 50)	Usual care (C) (n = 50)
Marital status
Single	23 (15.3)	10 (20.0)	10 (20.0)	3 (6.0)
Married/cohabiting	112 (74.7)	35 (70.0)	35 (70.0)	42 (84.0)
Separated/divorced	15 (10.0)	5 (10.0)	5 (10.0)	5 (10.0)
Educational level
Primary education	22 (14.7)	3 (6.0)	5 (10.0)	14 (28.0)
Lower secondary education	62 (41.3)	21 (42.0)	23 (46.0)	18 (36.0)
Upper secondary education	44 (29.3)	19 (38.0)	13 (26.0)	12 (24.0)
Vocational education	22 (14.6)	7 (14.0)	9 (18.0)	6 (12.0)
Occupation
Unemployed	75 (50.0)	27 (54.0)	21 (42.0)	27 (54.0)
Student	41 (27.3)	13 (26.0)	15 (30.0)	13 (26.0)
Part‐time employment	8 (5.3)	0 (0.0)	7 (14.0)	1 (2.0)
Full‐time employment	8 (5.3)	4 (8.0)	3 (6.0)	1 (2.0)
Self‐employed/own business	18 (12.0)	6 (12.0)	4 (8.0)	8 (16.0)
Monthly household income (THB)
≤ 5000	24 (16.0)	5 (10.0)	6 (12.0)	13 (26.0)
5001–10,000	63 (42.0)	17 (34.0)	22 (44.0)	24 (48.0)
10,001–15,000	44 (29.3)	17 (34.0)	16 (32.0)	11 (22.0)
15,001–20,000	14 (9.3)	7 (14.0)	5 (10.0)	2 (4.0)
≥ 20,001	5 (3.3)	4 (8.0)	1 (2.0)	0 (0.0)
Nipple assessment and correction during pregnancy
Normal	111 (74.0)	36 (72.0)	35 (70.0)	40 (80.0)
Abnormal and corrected	15 (10.0)	6 (12.0)	6 (12.0)	3 (6.0)
Abnormal and not corrected	24 (16.0)	8 (16.0)	9 (18.0)	7 (14.0)
Financial sufficiency
Sufficient	128 (85.3)	45 (90.0)	44 (88.0)	39 (78.0)
Insufficient	22 (14.7)	5 (10.0)	6 (12.0)	11 (22.0)
Family structure
Nuclear family	59 (39.3)	20 (40.0)	19 (38.0)	20 (40.0)
Extended family	91 (60.7)	30 (60.0)	31 (62.0)	30 (60.0)
Pregnancy intention
Planned	43 (28.7)	18 (36.0)	15 (30.0)	10 (20.0)
Unplanned	107 (71.3)	32 (64.0)	35 (70.0)	40 (80.0)
People influencing breastfeeding decisions
Mother
Yes	94 (62.7)	33 (66.0)	29 (58.0)	32 (64.0)
No	56 (37.3)	17 (34.0)	21 (42.0)	18 (36.0)
Husband
Yes	70 (46.7)	20 (40.0)	24 (48.0)	26 (52.0)
No	80 (53.3)	30 (60.0)	26 (52.0)	24 (48.0)
Nurse
Yes	50 (33.3)	17 (34.0)	18 (36.0)	15 (30.0)
No	100 (66.7)	33 (66.0)	32 (64.0)	35 (70.0)
Doctor
Yes	24 (16.0)	7 (14.0)	11 (22.0)	6 (12.0)
No	126 (84.0)	43 (86.0)	39 (78.0)	44 (88.0)
Social media
Yes	11 (7.3)	5 (10.0)	2 (4.0)	4 (8.0)
No	139 (92.7)	45 (90.0)	48 (96.0)	46 (92.0)

Note: Baseline characteristics are presented descriptively in n (%). No statistical comparisons were performed in accordance with CONSORT recommendations.

Overall, the three groups appeared comparable at baseline. Mean age ranged from 17.2 to 17.6 years across groups, and gestational age at the first antenatal care visit, planned maternity leave and intended duration of breastfeeding were similar. Baseline scores for breastfeeding knowledge, self‐efficacy, attitudes toward breastfeeding and knowledge of infant cues and responsiveness were also comparable across groups.

In terms of sociodemographic characteristics, most participants were married or cohabiting (74.7%), had lower secondary education (41.3%) and lived in extended family households (60.7%). The majority reported sufficient financial resources (85.3%) and unplanned pregnancies (71.3%). Family members, particularly mothers and partners, were commonly identified as key influences on breastfeeding decision‐making.

In the antenatal‐to‐postpartum application group, 3 participants (6.0%) did not initiate application use within 1 week and 1 participant (2.0%) did not complete all learning modules. In the postpartum‐only application group, 2 participants (4.0%) did not initiate application use within 1 week. All participants were included in the analysis as shown in Figure 1.

Figure 1.

Participants flow diagram.

3.2. Breastfeeding‐Related and Infant Responsiveness Outcomes

Mean scores for breastfeeding knowledge, attitudes toward breastfeeding, breastfeeding self‐efficacy and knowledge of infant cues and responsiveness across the three measurement points are presented in Table 5. Visual inspection of estimated marginal means demonstrated increasing trends over time for all outcomes in each group, with more pronounced improvements observed in the intervention groups (Figures 2, 3, 4, 5).

Table 5.

Breastfeeding‐related outcomes across time by study group (N = 150).

Outcome	Time point	Antenatal app (Tx1)	Postpartum app (Tx2)	Usual care
Breastfeeding knowledge	Pretest	11.64 (2.42)	11.82 (2.44)	11.02 (1.36)
	Post‐test 1	13.16 (3.09)	14.44 (2.46)	11.28 (1.90)
	Post‐test 2	13.52 (2.37)	14.62 (1.91)	12.96 (2.93)
Attitude toward breastfeeding	Pretest	57.04 (3.35)	56.34 (2.36)	55.82 (3.33)
	Post‐test 1	67.42 (4.95)	67.08 (6.87)	56.10 (4.23)
	Post‐test 2	69.92 (4.83)	68.24 (4.93)	58.62 (3.25)
Breastfeeding self‐efficacy	Pretest	48.12 (10.63)	48.68 (9.69)	46.14 (7.02)
	Post‐test 1	51.20 (9.34)	53.02 (9.11)	49.22 (6.03)
	Post‐test 2	54.00 (10.73)	55.84 (8.61)	52.12 (5.75)
Knowledge of infant cues and responsiveness	Pretest	9.88 (1.42)	9.86 (1.80)	9.52 (2.11)
	Post‐test 1	9.98 (1.23)	10.08 (1.44)	8.94 (0.86)
	Post‐test 2	10.38 (1.41)	10.06 (1.53)	9.68 (1.07)

Note: Values are presented as mean (SD).

Figure 2.

Attitude toward breastfeeding.

Figure 3.

Breastfeeding knowledge.

Figure 4.

Knowledge of infant cues and responsiveness. Note: Estimated marginal means of outcomes across time by study group.

Figure 5.

Breastfeeding self‐efficacy.

3.3. Effects of the Intervention on Breastfeeding Knowledge

Both intervention groups demonstrated higher breastfeeding knowledge scores compared with the usual care group when averaged across time (Table 6). The postpartum application group showed the greatest improvement (mean difference = 1.87, 95% CI 1.13–2.61), followed by the antenatal application group (mean difference = 1.02, 95% CI 0.27–1.76). Mean knowledge scores increased over time in all groups, with more pronounced gains observed in the intervention groups (Figure 3). Detailed repeated‐measures ANOVA results are presented in File S1.

Table 6.

Bonferroni‐adjusted pairwise comparisons between groups (averaged across time).

Outcome	Comparison	Mean difference	p‐value	95% CI
Breastfeeding knowledge	Tx1 vs. control	1.02	0.003	0.27–1.76
	Tx2 vs. control	1.87	< 0.001	1.13–2.61
Attitude toward breastfeeding	Tx1 vs. control	7.95	< 0.001	6.52–9.36
	Tx2 vs. control	7.04	< 0.001	5.62–8.46
Breastfeeding self‐efficacy	Tx1 vs. control	1.95	0.471	−1.36 to 1.91
	Tx2 vs. control	3.35	0.046	0.04–6.67
Knowledge of infant cues and responsiveness	Tx1 vs. control	0.70	0.002	0.21–1.19
	Tx2 vs. control	0.62	0.007	0.13–1.11

Note: Bonferroni‐adjusted pairwise comparisons were performed using estimated marginal means averaged across time. Values are mean differences with 95% CI. Tx1 indicates the antenatal intervention group, and Tx2 indicates the postpartum intervention group. Control refers to the usual care group. Statistically significant differences are indicated by p < 0.05.

3.4. Effects of the Intervention on Attitudes Toward Breastfeeding

Participants in both intervention groups reported substantially more positive attitudes toward breastfeeding compared with the usual care group (Table 6). The antenatal application group demonstrated the largest effect (mean difference = 7.95, 95% CI 6.52–9.36), followed by the postpartum application group (mean difference = 7.04, 95% CI 5.62–8.46). Attitude scores increased over time across all groups, with the greatest improvements observed among participants receiving the intervention (Figure 2). Detailed statistical results are provided in File S1.

3.5. Effects of the Intervention on Breastfeeding Self‐Efficacy

Breastfeeding self‐efficacy improved over time in all groups (Figure 5). However, differences between groups were small. Compared with the usual care group, the antenatal application group did not demonstrate a statistically significant difference (mean difference = 1.95, 95% CI − 1.36 to 1.91), while the postpartum application group showed a marginal improvement (mean difference = 3.35, 95% CI 0.04–6.67) (Table 6). Overall, trajectories of self‐efficacy were similar across groups. Detailed repeated‐measures results are presented in File S1.

3.6. Effects of the Intervention on Knowledge of Infant Cues and Responsiveness

Both intervention groups demonstrated higher knowledge of infant cues and responsiveness compared with the usual care group (Table 6). The antenatal application group showed a mean difference of 0.70 (95% CI 0.21–1.19), and the postpartum application group showed a mean difference of 0.62 (95% CI 0.13–1.11). Although improvements over time were observed across all groups, between‐group differences were modest (Figure 4). Detailed statistical results are provided in File S1.

Overall, the Enjoy‐Breastfeeding Mom smartphone application improved breastfeeding knowledge and attitudes among adolescent mothers, with the strongest effects observed for attitudes toward breastfeeding. Improvements in breastfeeding self‐efficacy and knowledge of infant cues were observed across all groups, although between‐group differences for these outcomes were less pronounced.

4. Discussion

This three‐arm randomised controlled trial evaluated the effectiveness of the Enjoy‐Breastfeeding Mom smartphone application on breastfeeding‐related knowledge, attitudes, breastfeeding self‐efficacy and maternal learning of infant cues and responsiveness among Thai adolescent mothers. Overall, the findings support the primary objective of the study by demonstrating that the digital intervention improved key cognitive and attitudinal outcomes, improvements in self‐efficacy were observed, but the intervention effects were less pronounced.

Consistent with the study objectives, both intervention groups showed significantly greater improvements in breastfeeding knowledge compared with usual care. This finding aligns with previous evidence indicating that structured education and counselling are effective in addressing informational gaps among adolescent mothers (Sipsma et al. 2015; De Oliveira et al. 2014). Digital delivery may be particularly suitable for adolescents, who frequently seek health information online and may prefer on‐demand access to educational content over traditional face‐to‐face consultations (Tang et al. 2019).

Breastfeeding attitudes also improved significantly in the intervention groups, with the antenatal‐to‐postpartum application group demonstrating the most favourable attitudinal outcomes. This finding suggests that earlier exposure to breastfeeding‐related information during pregnancy may facilitate gradual attitude formation before the onset of caregiving responsibilities. Previous studies have highlighted the importance of antenatal interventions in shaping breastfeeding intentions and perceptions, particularly among younger mothers (Renfrew et al. 2012; Yılmaz et al. 2016). According to the study, it was found that prenatal knowledge and attitudes significantly influence breastfeeding practices. High exposure to breastfeeding information and strong intentions were associated with better breastfeeding outcomes (Naja et al. 2022). The present findings extend this evidence by showing that antenatal engagement can be achieved effectively through a smartphone‐based platform.

Although breastfeeding self‐efficacy increased over time across all groups, no significant interaction between time and group was observed. This indicates that factors other than the intervention may have contributed to these improvements. One possible explanation is experiential learning through breastfeeding practice and routine postpartum support; however, this was not directly examined in the present study. Similar patterns have been reported in prior research, where self‐efficacy increased as mothers gained experience irrespective of intervention exposure (Dennis 2003; Demirci and Bogen 2017). Given that self‐efficacy is a confidence‐based construct, it is likely that more personalised or intensive strategies, such as real‐time coaching or peer support, may enhance intervention effects. This hypothesis warrants further investigation.

In line with the study objective addressing maternal learning of infant responsiveness, both intervention groups demonstrated greater improvements in knowledge of infant cues compared with usual care. Although the effect size was modest, this finding is clinically relevant, as adolescent mothers often report difficulty interpreting infant behaviours and tend to rely on informal sources rather than healthcare professionals for guidance (Nuampa et al. 2019). Teaching infant cue recognition alongside breastfeeding education may support more responsive feeding practices, which are central to effective breastfeeding and early mother–infant interaction (Barnard 1994). Although improvements in knowledge of infant cues and responsiveness were observed, this measure reflects cognitive understanding rather than observed caregiving behaviour. Therefore, the extent to which these improvements translate into responsive caregiving practices remains uncertain.

An important contribution of this study is the comparison of antenatal‐to‐postpartum versus postpartum‐only application use. The findings indicate that intervention timing influenced different outcomes rather than demonstrating a single superior approach. Antenatal‐to‐postpartum use was associated with more favourable breastfeeding attitudes, whereas postpartum‐only use resulted in greater gains in breastfeeding knowledge. This pattern suggests that adolescents' informational and motivational needs vary across the perinatal period. Attitudinal readiness may benefit from earlier engagement, while practical knowledge acquisition may be more salient once breastfeeding has begun. These findings are consistent with emerging evidence that combined prenatal and postnatal digital interventions are more effective than those delivered in a single period (Fan et al. 2024).

The findings support the integration of adolescent‐tailored, nurse‐supported smartphone applications into routine nursing care. Digital interventions may extend breastfeeding support beyond clinic settings, enhance continuity of care, and reduce inequities in access to breastfeeding education, particularly in resource‐constrained contexts. Importantly, incorporating infant responsiveness content alongside breastfeeding education reflects a holistic nursing approach to early maternal–infant care.

However, this study primarily reflects improvements in proximal cognitive and attitudinal outcomes, including breastfeeding knowledge, attitudes, self‐efficacy and learning of infant responsiveness. While these factors are recognised as important precursors of breastfeeding behaviour, the present study was not designed to evaluate sustained behavioural or clinical outcomes. Therefore, the extent to which these improvements translate into long‐term breastfeeding practices remains uncertain and warrants further investigation. Moreover, this study has several limitations. The follow‐up period was limited to 30 days postpartum, and infant feeding practices were only briefly assessed, limiting evaluation of the sustainability of behavioural outcomes. Outcomes were self‐reported and may be subject to recall or social desirability bias. Regular contact with participants and repeated assessments may also have influenced behaviours (Hawthorne effect), contributing to improvements across all groups. Participant blinding was not feasible, although outcome assessment and analysis were blinded. Participants were recruited from tertiary hospitals with well‐established breastfeeding support services and included only primigravida adolescents with uncomplicated pregnancies, which may limit generalisability to other settings and populations.

Future research should examine whether the benefits of digital breastfeeding interventions are sustained beyond the early postpartum period using longer follow‐up and objective behavioural measures. Further studies are also needed to clarify how such interventions influence breastfeeding self‐efficacy and to test their implementation and scalability across different healthcare settings.

5. Conclusions

This multicentre randomised controlled trial demonstrates that the Enjoy‐Breastfeeding Mom smartphone application is an effective adjunct to routine nursing care for Thai adolescent mothers. The intervention improved breastfeeding‐related knowledge, attitudes, and maternal learning of infant cues and responsiveness, with differential effects observed according to the timing of application use. While breastfeeding self‐efficacy increased over time across all groups, the digital intervention did not produce additional short‐term effects beyond usual care. These findings highlight the potential of adolescent‐tailored, nurse‐supported mobile health interventions to strengthen breastfeeding education and early responsive caregiving. Integrating such digital tools into perinatal nursing practice may help address gaps in breastfeeding support for young mothers. Further research with longer follow‐up is warranted to examine sustained behavioural outcomes and inform broader implementation.

Author Contributions

Sasitara Nuampa was involved in conceptualising the study, developing the study methodology, supervision, project administration, and funding acquisition. Sasitara Nuampa, Metpapha Sudphet and Sutthirak Bubpawong performed data collection. All authors contributed to data interpretation, while Sasitara Nuampa led the overall analysis process. Sasitara Nuampa wrote the original draft. Manassawee Srimoragot and Nantakarn Maneejeak reviewed and edited the manuscript. All authors read and approved the final manuscript.

Disclosure

The statistics were checked prior to submission by an expert statistician (Sutthisak Srisawad; sutthisak.sri@mahidol.ac.th).

Consent

Written informed consent was obtained from all participants prior to study enrolment, in accordance with institutional and national ethical requirements. Participation was voluntary, and participants could withdraw from the study at any time without any consequences to their care or services received.

Conflicts of Interest

The authors declare no conflicts of interest.

Supporting information

Supporting File 1.

Supporting File 2.

Data Availability Statement

De‐identified data supporting the findings of this study are available from the corresponding author upon reasonable request. The data are not publicly available due to privacy or ethical restrictions.