Exclusive breastfeeding (EBF) is very important for a child's early life because it can protect around 800,000 children under 5 from the risk of death and various diseases [1]. Breastmilk has active capabilities that can be adapted optimally to the baby's needs, and it is the only nutrition within the first six months of life [2]. EBF practice can serve as a major component during the older period, such as improving cognitive function and intelligence, preventing obesity, and reducing the risk of cardiovascular and metabolic diseases [3,4]. However, the rate of EBF practice in the world is only around 44%, with less than one in two children exclusively breastfed [5].

The low practice of EBF is more severe among young mothers compared to older mothers. In India, EBF coverage among young teenage mothers is only 58.7% [6], while in Bangladesh, it is only 53% [7]. In Indonesia, the proportion of EBF among adolescent mothers aged 15–19 years is only 50.9%, while in the older age group, it is relatively higher, namely 53.9% [8]. This evidence implies that even though abundant measures have been taken to promote EBF practice, it is not adequate to be sensitive towards specific groups, such as young mothers. Therefore, any EBF program must be sensitive to vulnerable groups. Adolescent-oriented intervention could be expected to raise their knowledge, attitude, and practice of EBF [9].

As a part of motherhood experience, EBF is quite challenging for all mothers, and the challenges are more burdensome for younger ones. Aside from facing various lactation problems, young mothers often receive social stigma against breastfeeding in public [10,11]. One intervention to promote EBF is encouraging postnatal care (PNC), which includes counseling about breastfeeding and understanding breastfeeding problems [12]. A shred of evidence suggests that visiting PNC within two days after delivery has benefits in reducing non-EBF compared to no visits at all [13]. However, limited evidence identified the service quality regarding EBF practice during the PNC visit.

This study explored the relationship between proper PNC and EBF practice among young Indonesian mothers. The assumption is that proper PNC will link to a greater chance of EBF practice among young mothers in Indonesia. Aside from generating further evidence about the motherhood experiences among young mothers, our study has the potential to explore the gap in breastfeeding interventions that have been implanted till today, which might not target the vulnerable population. The present study's findings could be recommendations for policymakers and other stakeholders to improve the programs based on scientific evidence and precise data.

This study has proven around 51.6% of infants born to young mothers were exclusively breastfed. According to sample characteristics, the distribution of EBF practice only differed significantly (P<0.05) by wealth index and number of living children. The present study demonstrates that some factors linked to EBF practice among young mothers were marital status, working status, and wealth index. The primary independent variable, proper PNC was not significantly associated with EBF practice in all age groups; instead, it became noteworthy factors for infants delivered by adolescent mothers aged 15 to 19.

Being married could raise the probability of an infant being breastfed exclusively up to threefold higher among young mothers. Parallel with a previous study conducted in Ethiopia [18], the supportive environment from a spouse or another family member may encourage the mother to breastfeed her baby devotedly [19]. In contrast, unmarried young mothers are underprivileged in this context. The reason is probably caused by facing problems accessing adequate health services, as they often deal with negative stigma [20] and perceived judgement of premarital sex [21]. These issues demonstrate the necessity to put more effort and tailored intervention among young unmarried mothers, who are often neglected. Moreover, family involvement becomes an essential consideration when proposing adolescent-oriented interventions.

As explained in our study and the previous one [22], an infant whose young mother is employed possesses a negative association with EBF practice [17]. Furthermore, in Indonesia, less than 25% of working mothers utilize the lactation service, and only one-tenth of them can obtain its benefits [23]. Although breastfeeding promotions and campaigns have been implemented in the working environment [24], our findings indicate the uptake of lactation services is under the line, particularly among young mothers. Working mothers who experience difficulties in breastfeeding or expressing breastmilk in the workplace [17] choose to purchase formula milk to feed their infants because breastmilk substitutes such as infant formula are highly accessible and marketed largely across regions in Indonesia [25]. As an impact, we found wealthy young mothers can afford to buy breastmilk substitutes compared to poor ones, resulting in suboptimum breastfeeding practice.

In the present study, infants born to adolescent mothers aged 15–19 who properly received postnatal services had an approximately eightfold higher chance of obtaining breastmilk exclusively. It sheds light on the quality of PNC as a careful consideration since only attending PNC within two days after delivery cannot be measured as a qualified service [26]. A study suggests that increasing the likelihood of breastfeeding maintenance at six months of an infant’s life necessitates lactation services in PNC [27]. The present study demonstrates the importance of breastfeeding initiation after delivery, lactation counseling, and breastfeeding observation to emphasize EBF practice among infants born to adolescent mothers.

Postnatal education is an essential means of supporting breastfeeding behavior in adolescent mothers who still develop their capacity for comprehensive awareness. It allows them to immediately comprehend what to do while practicing with the infant directly [28]. A higher chance of EBF practice is observed among mothers who initiate breastfeeding soon after delivery [29] and counsel on breastfeeding during postnatal period [30]. However, the majority of adolescent mothers are reported to have trouble starting to breastfeed [31] and feel abandoned when healthcare providers just provide advice instead of giving them direct observation and guidance while breastfeeding [32]. Thus, providing a comprehensive postnatal service, which includes lactation management within 2 days after delivery, is imperative to ensure the qualified service received by mother-infant dyad, particularly among adolescents.

Our study highlights the encouragement of EBF practice by providing a positive postnatal experience towards adolescent mothers and their infants. To the extent of our knowledge, this is the first study identifying proper services acquired by adolescent mothers during early postnatal period in correlation with EBF practice. This study used IDHS 2017 data, which is nationally representative, so the results can be generalized to Indonesian population. However, there are some restrictions in interpreting the findings of the study. First, our study cannot provide a temporal causal-effect relationship since both predictors and outcomes were observed simultaneously. Thus, it only describes the effect size of association between predictors and outcome. Secondly, although data is derived from a population-based and nationwide survey, the retrieved final sample is only around one per cent of the total IDHS 2017 sample size. A small final sample size might influence confidence interval and level of significance values. Further research in prospective design can be beneficial to evaluate the adolescent mother's parenthood behavior, particularly since pregnancy. A deeper understanding of sociocultural context is also significant to determine the broader influence of family and society on infant feeding practices among vulnerable groups.

In conclusion, this study suggests that adolescent mothers in Indonesia need proper services during early postnatal period in maintaining EBF practice for their infants. Proper PNC should comprise lactation management services like early initiation of breastfeeding, lactation counseling, and breastfeeding observation in order to serve a high-quality service. Concerning the sociocultural aspects of vulnerable populations is advantageous in proposing adolescent-oriented intervention. Looking at the findings in this study, policymakers and stakeholders are in charge of putting more effort into breastfeeding promotion among younger mothers. Adolescent mothers who are already burdened experiencing their motherhood should be accompanied by equitable and qualified services to prevent adverse impacts on their infant’s health.