This study examines the biological, social, and environmental determinants of low birth weight and stunting, using data from the 2005-06 Zimbabwe Demographic and Health Survey (ZDHS). In Zimbabwe the prevalence of stunting among children age 0-59 months has increased over the past decade, from 21% in the 1994 ZDHS to 28% in 2005-06. More than one infant in every 10 has low birth weight. Understanding the factors that contribute to high prevalence of low birth weight and stunting is important for child development and child survival programming and intervention.
The study sample consists of 5,231 children who were born within the five years preceding the 2005-06 ZDHS and whose mothers were interviewed in the survey. Analyses focus on children age 0-59 months who were weighed at birth (for analyses of birth weight) and children age 6-59 months whose weight and height were measured at the time of survey (for analyses of stunting). Multiple logistic regression analysis was used to assess the independent association of each explanatory variable with the likelihood of a child having low birth weight or being stunted.
Our results show that of multiple-birth children, 60% have low birth weight and at the time of the survey 58% are stunted. Higher maternal body mass index and birth spacing are protective against stunting. After controlling for characteristics of the mother and the child, no household or socioeconomic and environmental characteristics are significantly associated with low birth weight. Among the younger children age 6-23 months the odds of being stunted increase 11% with each additional month of age, whereas among the older children age 24-59 months each additional month is associated with a 2% decrease in the odds. Also, the determinants of stunting are stronger and more significant among younger than older children. Low birth weight children are more likely to be stunted in early childhood. Vitamin A supplementation is protective against stunting among older children even after controlling for immunization. Older children living in a household with access to a toilet are less likely to be stunted, after controlling for other covariates, including access to a protected water source, maternal education, and household wealth status. In a sub-analysis of youngest children age 6-23 months, there is no significant association between the adequacy of feeding practices and stunting.
Our findings suggest that interventions to address child undernutrition should begin before childbirth and continue through early childhood. Efforts to improve maternal nutrition, family planning, and antenatal care as well as access to Vitamin A supplementation and the sanitary environment are important, and all play key roles at different stages of a child’s early life.