Factors contributing to the reduction in childhood stunting in Bangladesh: a pooled data analysis from the Bangladesh demographic and health surveys of 2004 and 2017–18

Over the last two decades, different policies and programs have worked together to uplift the success of child survival across the globe [1‐4]. Despite these improvements, deprivation from adequate nutrition along with recurrent illness among children has paved the way for a critical health issue [5‐7]. Stunting, defined by the WHO [8] as “impaired growth and development that children experiences from poor nutrition, repeated infection and inadequate psychosocial simulation” is one of the grratest child health challenges which leaves a life-long mark on the individual [6, 7].

Globally, approximately 149 million children experience stunting before their fifth birthday [9]. The Global Overview Child Malnutrition Regional Trends Report of UNICEF shows that in Asia stunting still aflicts more than half of the Under-5 (U5) children (55%. More specifically, the situation of children in South Asian countries is alarming. Bangladesh is one such country which has experienced, throughout the decades, many ups and downs in the prevalence of stunted children. Being in a frequent natural disaster-prone area, the possibility of infectious diseases and inadequate nutrition are higher among the population [10, 11]. During the 1974 famine, the country experienced the highest (71%) Under-5 rates of stunting [12]. This has decreased to 31% in 2017 [13]. The country had made remarkable progress in reducing the prevalence of stunting, but it is still far from the 15% threshold marked by World Health Organization for an emergency situation in stunting for any country [14].

Extant research had repeatdly pointed out the prevalence of stunting in U5 children and its associated risk factors in Bangladesh [12, 15‐20]. Studies have revealed that the effect of childhood stunting is long lasting and, in most cases, irreversible. Stunting is associated with lower mental capacity, slower cognitive development, and low school performance that will impact adult productivity. It is also related with an increase in mortality rates and an overall deteriotaon of the children’s health status [6, 21‐25]. And these challenges can further topple the growth and development of a family, society and country as a whole.

Stunting develops at very early age due to unhealthy environments experienced by both mother and child [25, 26]. Previous literature in Bangladesh has linked the risk of under-five stunting with socio-demographic, healthcare services and nutrition-related factors [15, 19, 27, 28]. Although focusing on nutrition and recurrent diseases among children have helped in improving their health, there is the necessity to focus on the first and foremost proximal setting of a child: the family. A community-level cross-sectional study also revealed that over 85% of main caregivers in Bangladesh households are mothers who play an influential role in arranging and providing food for their children [29]. A study, using multilevel approach, has clearly shown that the risk of stunting was higher among children whose parents have the lower educational level and poorest wealth index, if the age of mother at the birth of the first child was below 20 years and if child’s age range was 36–47 months [16]. Furthermore, in Bangladesh research has highligthed the importance of improved water source and sanitation facility in a household towards child health [27, 30]. Moreover, even if the public health services are advanced, household wealth inequalityis strongly associated with childhood growth faltering [28]. Household wealth inequality measures the unequal economic distribution across the households which affects distinctly the food availability, access to health services, morbidity and mortality among the various sections of society. It was worth noting that children from the poorest household were thrice more likely to experience adverse stunting than those who reside in the wealthiest households. A cross country study has shown that, between 1997 and 2007, Bangladesh has recorded a fairly rapid progress against malnutrition among the low-and-middle-income countries [31] and has sparked interest about which contributing determinants of this reduction are.

Therefore, the main goal of this study is to identify the crucial factors that contributed to the reduction of stunting among U5 children in Bangladesh, between 2004 and 2017–18. The rationale for this analysis is threefold: i) Over the years, nutritional commitments at global platform have helped the countries across the world either to achieve their desired goal or to move one step forward without achieving fully. Such success or failure of programs help to modify the strategies and policies of the government. A country like Bangladesh which has observed many ups and downs in under-5 stunting status, there a study which can provide a clear picture of potential drivers is the need-of-the-hour. Although the past evidence shows the determinants of under-5 stunting status of Bangladeshi children, there is need for recent evidence which this study brings out.; ii), ample evidence shows the association of lower stunting status of children with the higher education and wealth status of family [32]. Studies have also pointed towards the key role of sanitation and demographic factors as the drivers of change. However, minimal evidence shows the role of the mother’s health on child stunting status, which have been explored in the present study; iii), with the limitations in nutrition-related information for under-five children in Bangladesh, this study pronounced to consider family (i.e. mother and father) and community related characteristics along with the household socio-economic and demographic factors. Thus, using two rounds of Bangladesh Demographic and Health Survey and Fairlie decomposition technique [33], this study explores the contributing factors of reduction in under-five stunting status in Bangladesh.

Since stunting replicates the accumulative outcome of socio-economic, health and nutritional drawbacks that vary over time [39, 40], the continuous evaluation of underlying factors may help boost the pace of its reduction. In spite of substantial achievements in reducing the prevalence rates of stunting among under-five children in Bangladesh through various intervention programs, the findings of this study with 30.7% children still being stunted with marked regional variations underscore the need for further improvement in the children’s nutritional status in the country.

In the present study, we found that children of age group 23–47 months, with higher birth order, born to mothers with low BMI, to mothers and fathers with no formal education and belonging to households with poor sanitation and poorest wealth index were significantly more likely to be stunted. Results from binary logistic regression show that as children grow up they become more likely to be stunted. Similarly, under five children who were most likely to be stunted belonged to the age of 23–47 months. And the result is consistent with recent studies in Bangladesh [16, 41, 42]. Higher prevalence of stunting among children who aged 2 year and older can be explained by inapropriated or untimely initiation of complementary feeding and lack of dietary diversity and nutritional knowledge that are found to be major risk factors of stunting [43, 44]. Furthermore, the finding that fifth or higher order birth is related to a greater prevalence of stunting is similar to another study in Bengladesh [45], and is so probably due to lesser time to extend care equally to each of the children. It is also noted that having a higher number of siblings in a household may cause growth retardation in children due to competition for limited available nutritional resources [46]. However, the decadel decline in children with higher birth order possibly due to declining fertility and growing number of small-sized families has significantly contributed to the observed decrease in childhood stunting in the present study.

Studies in low-and-middle income countries reveal that the child is inherited with how he/she was cared both in the womb and during childhood and there exists an intergenerational cycle of health and nutrition [47‐49]. The study result suggests that healthier mothers have lower risk of having stunted children. The finding that the maternal higher BMI as a protective predictor for childhood stunting is consistent with previous studies [50‐52]. It is argued that with good nutritional status, mothers can confirm better breastfeeding and react to pregnancy-related stressors effectively [42, 53]. In addition, current study found that mother’s low BMI had a significant and largest contribution to decadel decrease in childhood stunting compared to all other factors. It reflects the findings of recent studies in Bengladesh on the success of delivering multiple interventions for maternal nutrition and health [54‐56].

Education of parents is found to be another significant contributer to the decrease in the prevalence of stunting among the children below 5 years, indicating the improvements in overall socioeconomic indicators of the general population in the country. Again, education being a significant predictor shows that higher levels of education can act as a preventive factor against child stunting. Thus, children may become stunted due to their mothers’ or fathers’ lower educational status and lack of sources of knowledge on child nutrition. Evidence suggests that education always plays a positive role in health and diseases [57, 58]. Studies conducted in low and middle income countries also reveal that educated mothers tend to be older at their first birth and are more knowledgeable about health, nutrition, hygiene and care practices for children [59‐61]. In addition, a recent study shows that maternal awareness on childfeeding practices also led to improved nutritional status of young children [62]. Educated parents can further contribute to a better household economic status that is supportive of providing sufficient nutritional diet to their children. Additionally, they tend to have have greater access to media that make them better able to use available health-care facilities and more adept at keeping their environment clean [52, 63].

Furthermore, nutritional status of children is considered as an indicator that reflects the household economic condition. This study also shows that children from households with poorest wealth index are most likely to be stunted in consistence with previous studies conducted in other countries [42, 61, 64, 65]. This can be attributed to the fact that households with higher socioeconomic status may have more ability to allocate necessary resources regarding nutrition for their children. Also, reasonable allocation of resources may improve their children’s health conditions by minimizing multiple health risks. Consistent with past studies [15, 60, 66], access to improved toilet facility in the households was found as a significant determinant of stunting among under-five children. Poor sanitation facilities have negative impact on child’s nutritional status through pathways such as loss of appetite, loss of host tissues and maldigestion, resulting in a vicious cycle of growth faltering in childhood [67]. It is also documented that an adverse environment may cause differences in the metabolism of micronutrients in children and potentially limit their ability to develop into healthy adults [30, 68].

Finally, we observed large regional variations in the prevalence of stunting among under-five children, where highest prevalence was found in the Sylhet administrative division. Although the Sylhet division is established in previous studies as poorest performing region in most of the health-related indicators including child stunting [52, 69], the situation still remains the same. Thus, region specific studies are warranted for seeking explanations of why the stunting of Bengladeshi children varies across different divisions.

This study has certain limitations. Firstly, the study was based on cross-sectional data, which failed to establish a casual relationship. Importantly, the study assumes that stunting is due primarily to nutrition and any of the nutritional variables were not included in the analysis. Another major limitation is that this study has particularly focused only some selected factors. The factors, such as duration of breast feeding, household size, use of iodized salt and dietary diversity, among others that may also affect stunting among children were not analysed.

The strenths of this study the results identified the most vital risk factors of stunting, which will add to the available literature on the association of socioeconomic and demographic variables and parents’ characteristics with stunting of under five children in Bengladesh. Besides, the survey data used in the present analysis was based on a two-stage stratified sampling of households and was designed to generate representative results for the country as a whole and for each of the seven administrative divisions.

The results of the study strongly highlight the importance of taking steps to make people educated and to reduce household wealth inequality to improve nutritional status of children. In order to achieve further reduction in stunting among under-five children in Bangladesh, target interventions that would benefit the socioeconomically backward population are required. Results also suggest that the policymakers should develop an effective program to improve the maternal education and health and increase awareness of parents about the standard children’s height and weight according to their age and gender. Despite making gains in macro level health and development indicators, there is a need to address the underlying issues of child malnutrition in Bangladesh. Therefore, policymakers need to revisit and expand current mother-child specific programs and interventions targeting vulnerable regions and households. Also, government may take necessary steps to make women of reproductive age aware about adverse effects of higher birth order in their later ages and its adverse effects on child health.