This was a quasi-experimental study with 116 respondents who were grouped into control and intervention groups. Respondents were recruited using consecutive sampling at 2 locations: Lebak, Banten, and Cimanggis, Bogor. Eligible participants were postpartum mothers starting from the seventh day after delivery. Four questionnaires were used to evaluate the effectiveness of the intervention through quantitative analysis: questionnaire A covered respondent data and characteristics; questionnaire B covered breastfeeding and infant weight data on the first day and on the seventh day after the intervention (assessment of feeding practices used a 24-hour recall question); questionnaire C evaluated maternal knowledge of exclusive breastfeeding practices (Cronbach α=0.801); and questionnaire D, which has been previously used and validated by Budiati et al [15] (validity coefficient=0.976), assessed the perception of the adequacy of breastfeeding (Multimedia Appendix 1). The Perceived Insufficient Milk (PIM) instrument [16] and calibrated baby weight scales were also used.

The culturally based intervention was developed during the model development stage based on an initial analysis and literature review. A culturally sensitive intervention module was created as a reference for post-caesarean mothers, husbands, families, and local health care volunteers. The intervention was implemented through training and assistance for mothers and families to support breastfeeding practices in a culturally appropriate manner. The modules covered breastfeeding benefits and content, breast care, proper attachment, lactation management, family empowerment and support, the role of health workers, and the involvement of community, traditional, and religious leaders. The intervention aimed to improve breastfeeding practices and breast milk adequacy, reflected in infant weight gain.

Data were analyzed using the Kolmogorov-Smirnov test, unpaired and paired t tests, and logistic regression.

Ethical approval for this research was obtained from the Faculty of Nursing Ethics Committee at the University of Indonesia (296/UN2.F12.D/HKP.02.04/2018). All participants provided written informed consent prior to enrollment. Participants were not offered any compensation for their participation in this study.

The culturally based intervention model was developed based on a stage 1 analysis and literature study. This model then became a reference for mothers, husbands, their families, and local health care volunteers. Training and assistance were provided to the mothers and families in implementing culturally sensitive care after caesarean delivery to promote breastfeeding practices, which we expected would result in increased breast milk production and adequate infant weight.

The modules shown in Figure 1 were developed during the stage 1 analysis to explain the benefits of breast milk, breast care during breastfeeding, proper attachment during breastfeeding, and breastfeeding management. Other modules addressed transcultural care and the role of the community in supporting post-caesarean mothers.

Participants were included if they were post-caesarean mothers who had given birth to a full-term baby with a weight ≥2500 grams and an Apgar score ≥8, were living with their spouse at the same residence, and were able to write and communicate verbally and non-verbally. Mothers with a critical medical condition that required emergency intervention and who could not fully participate in the research process were excluded.

The culturally based intervention was carried out in 3 sessions of 60 minutes each. Training and assistance were scheduled 3 times for local health care volunteers, 3 times for family members, and 2 times for professional health care workers. A pretest was conducted at the first intervention session and repeated at the final session as a posttest to evaluate intervention outcomes. Meanwhile, the control group received conventional postpartum care delivery by health care professionals following the national maternal and child health reference (Buku Kesehatan Ibu dan Anak/KIA booklet) without any additional cultural components.

The majority of respondents in this study did not perform skin-to-skin contact, even though it is the first step in successful breastfeeding. This is consistent with research indicating that the caesarean process is associated with delays in both skin-to-skin contact and lactogenesis [7,8,17,18]. Disruption to the lactogenesis process can be influenced by the effects of decreased oxytocin secretion or stress in mothers who have undergone a caesarean section, resulting in decreased breast milk production in the mother [19,20].

According to Budiati and Setyowati [21], although mothers may have good knowledge, they still face many environmental obstacles to practicing the desired behavior. Also, many mothers may recognize the benefits of exclusive breastfeeding, but they are constrained by sociocultural barriers, such as a lack of family support, gender roles, traditional customs, and body image [22].

Our culturally based intervention combined several modules proven to affect breast milk adequacy and infant weight. This is in line with previous research on a baby-friendly hospital initiative that combined two or more strategies, finding that it was sustainable in different hospitals and in the community [23].

Indonesian culture is based on kinship, and mothers’ decisions about breastfeeding are often influenced by the people around them, such as their own mothers, parents-in-law, and husbands [22]. Thus, subjective norms are also a key component of successful breastfeeding [24,25]. Breastfeeding control refers to a mother’s self-confidence and ability to practice breastfeeding.

During the model development stage, preliminary qualitative findings revealed that mothers initially desired exclusive breastfeeding but felt helpless and deferred to family members who introduced formula milk when breast milk appeared insufficient or the infant was fussy. This is consistent with previous research that mentioned how social influence affects mothers’ decisions to breastfeed during the first 3 days after delivery [26]. That study showed that social norms or influence come from family, neighbors, and close relatives. These people’s beliefs can unintentionally influence the mother’s beliefs. If the family, neighbors, or close relatives feel that the mother should breastfeed exclusively, then she will do so. Conversely, mothers who receive opposing social pressure share the same perceptions as the people around them [27].

The results of this study showed that the average weight of infants in the intervention group differed before and after the culturally based intervention. This is in line with previous research regarding the effectiveness of breastfeeding education on infant weight and breastfeeding mothers’ self-efficacy [28,29]. Other research on low-birth-weight infants highlighted that health education combined with peer support could increase maternal confidence and infant weight through the implementation of “kangaroo mother” care (ie, increased skin-to-skin contact) and lead to increased breastfeeding [30].

The findings of this study highlight the important role of cultural and social factors in shaping exclusive breastfeeding practices. This is consistent with findings from Herawati et al [10], who reported that breastfeeding beliefs and cultural factors significantly influenced exclusive breastfeeding success in Banten and West Java. These results suggest that cultural influences on breastfeeding may vary across regions, depending on local beliefs, family structures, and social dynamics.

Furthermore, the results align with a global scoping review by Badanta et al [31], which demonstrated that cultural beliefs and social norms strongly affect women’s breastfeeding behaviors. Common cultural perceptions, such as beliefs regarding the quality of breast milk or the value of colostrum, as well as family and social pressures, were identified as barriers to exclusive breastfeeding. By integrating culturally based approaches into the intervention, this study supports the growing evidence that breastfeeding promotion strategies should not focus solely on health education but also address underlying cultural beliefs and social contexts.

A limitation of this study was that several participants dropped out due to health problems after being exposed to COVID-19. In addition, there were confounding factors, such as self-efficacy, nutrition, and the use of galactagogues by mothers, that were difficult to control and may have affected the adequacy of breast milk production.

Providing a program that combines several strategies to promote breastfeeding among mothers can increase exclusive breastfeeding, especially among mothers who have undergone a caesarean delivery. Our culturally based intervention could be applied in health care facilities, such as community health centers (puskesmas) and hospitals, as a first-line strategy in the care of pregnant women. In addition to medical practices, care and cultural interventions are factors that affect mothers’ decisions in choosing a delivery method. Culturally based interventions are often overlooked by health care workers, and developing new guidance and policies will increase mothers’ awareness of exclusive breastfeeding practices, especially among post-caesarean mothers.

This quasi-experimental study was designed to evaluate the effectiveness of a culturally based intervention to increase breast milk adequacy and infant weight. The intervention increased the odds of perceiving breastfeeding as “very sufficient” by 2.53 times (odds ratio 2.53, 95% CI 1.36-4.73), after controlling for belief in breastfeeding myths and family support, compared to mothers who did not receive the intervention. The intervention improved mothers’ and family members’ capacity to differentiate evidence-based breastfeeding practices from culturally held myths, resulting in more informed and supportive family engagement during the post-caesarean recovery period.