Predictors of stunting among children 6–59 months of age in Sodo Zuria District, South Ethiopia: a community based cross-sectional study

Stunting (low height-for-age) is a sign of chronic undernutrition that reflects failure to receive adequate nutrition over a long period. Children are regarded as stunted when their height-for-age Z-score (HAZ) is below minus two standard deviations (−2SD) from the median of the reference population [1]. Stunting reflects failure to get adequate nutrition over a long period of time and it can be affected by recurrent and chronic illness [2].

Malnutrition leads to serious public health and economic risks, and improvements in nutrition will contribute significantly to reducing poverty, and to achieving health, education, and employment goals [3]. Child undernutrition is highly prevalent in low and middle-income countries and substantially increases mortality and overall disease burden [4]. Globally, 161 million (25%) children under-5 years of age were estimated to be stunted and one third of all stunted children lived in Africa [2]. The highest prevalence of stunting is reported in South Asia (36%) and Sub-Saharan Africa (34%) [5]. In Ethiopia the prevalence of stunting is 38% [1], ranking the country among the top both in sub Saharan Africa and the World.

The World Health Organization [WHO] adopted a resolution with a target to reduce the number of stunted children under-five by 40% in 2025. However, at current rates of progress, stunting level will decrease by 26% in 2025 [6]. Similarly, despite the decline in the rate of stunting from 47% (2005) [7] to 38% (2016) [1] in Ethiopia, the prevalence is still high and needs immense efforts to achieve the target set to reduce the prevalence to 26% in 2020 [8]. Childhood stunting varies between localities due to individual and community-level factors [9, 10] and the factors associated with stunting vary by the dominant livelihood practice in the community [11]. However, there are no documented studies to identify the factors associated with stunting in the study area. Thus, the aim of this study was to determine the prevalence of stunting and identify factors associated with it in Sodo Zuria district in South Ethiopia.

The prevalence of stunting documented in this study was 24.9%, which is lower than the national prevalence (38%) and the prevalence level of South Ethiopia (39%) [1]. Higher prevalence levels were reported in Eastern Ethiopia (45.8%) [12], Northwest Ethiopia (38.3%) [13], Nigeria (36.7%) [14] and Nepal (38%) [15]. This difference might be because we used NCHS growth standard and those studies used WHO growth standard (which is known to increase the prevalence of under nutrition specially stunting as compared to NCHS growth standard) [16].

Unlike many other study findings, this study documented that the odds of being stunted was higher for females as compared to males. This finding is different from other study findings from Ethiopia, Nigeria, Tanzania and Uganda where males have higher risk of being stunted [14, 17–19]. On the other hand, in favor of our finding a study from Eastern Ethiopia reported that females had higher chance of being stunted [20]. This may be due to cultural issues, gender preference and differential feeding practice which neglects girls [21–23]. Girls are more likely than boys to experience food insecurity due to selective availability of the limited food for boys than girls in Ethiopia [24]. However, a study in India and Pakistan found no statistically significant association between gender and stunting [25, 26].

We have found that the odd of being stunted was higher for children above 12 months as compared to children 6–11 months. Other similar studies conducted in Nigeria, Ethiopia and Pakistan reported that stunting was significantly associated with age above 12 months [26–29]. The trend of stunting peaks for each group of children age up to 35 months and then declines for children 36–47 months of age. The possible explanations are when children are becoming mobile; they are exposed to contaminants in water, food and soil and they ingest them. Inappropriate complementary feeding and introducing children directly to household diet is another possible reason.

Children from middle- and high-income households had less chance of being stunted. This was in agreement with similar study findings in Southwest Ethiopia [30], Northwest Ethiopia [28, 31], Tanzania [18], Nigeria [14] and Nepal [30] where children from the poor wealth quintile had higher odds of being stunted compared with children from the rich wealth quintiles. Children from poorest households had a higher risk of being stunted compared to those from middle- and high-income households [18, 27, 31, 32]. Increased income improves dietary diversity, which in turn improves nutrient intake and nutritional status [33]. Poor wealth status also negatively affects household food access, sanitation and availability of improved water sources.

Children born to mothers who do not use family planning methods had a higher odds of being stunted compared to those mothers who use family planning methods. Mothers who do not use family planning will have large family size and a short birth interval. Studies from South and Southwest Ethiopia [30, 34], Northern Ethiopia [35], Mozambique [36] and Ghana [37] documented that children living in large family size had an increased risk of being stunted as compared to those from small family size. The possible explanations are that having large family size affects intra-household availability of resources and child caring practice. Short birth interval also has an adverse effect on child nutrition and quality of care. It also leads to intrauterine growth retardation, preterm birth and low birth weight which in turn lead to stunting.

In consistence with studies from Nigeria, South and Northwest Ethiopia, children with diarrheal morbidity 2 weeks prior to the study had a higher chance of being stunted [14, 19, 38, 39]. Diarrhea results in poor appetite, digestion problem and malabsorption and malnutrition children on the other hand have severe episodes of diarrhea.

We have found that pre-lacteal feeding was a predictor of stunting. This is consistent with a study from Southern and Northern Ethiopia [19, 39, 40]. The plausible reason may be stunted children are less likely to be introduced to complementary feeding at appropriate age [18]. The other likely reason is that pre-lacteal feeding has a negative effect on breastfeeding which in turn places children at higher risk of under-nourishment.

The magnitude of stunting in the current study was low. Stunting was significantly associated with being female, age above 12 months, low household income status, mother’s not using family planning and pre-lacteal feeding. Gender-based policies should be enacted in child feeding practice. Interventions should focus on the utilization of family planning and appropriate child caring and feeding practices should be implemented according to the infant and young child feeding recommendations. Water, sanitation and hygiene interventions need to be strengthened to reduce the occurrence of diarrheal morbidity and poverty alleviation interventions should be implemented.