Determinants of low birth weight in Zambia: evidence from the 2007 and 2013/14 Zambia demographic and health surveys (zdhs)

Abstract

Of the estimated 130 million infants born each year worldwide, 20 million are born with a birthweight below 2.5 kg referred to as low birth weight (LBW) and about 97 percent of these births are occurring in the developing countries. The prevalence of LBW results from a complex chain of socio-economic and demographic, reproductive behavior, nutritional and environmental factors. In Zambia, the prevalence has been static for 7 years. This study aimed to estimate the prevalence of LBW across 2007 and 2013/14 Zambia Demographic and Health Survey by province and identify the determinants pf LBW in Zambia in 2013/14. The study was a cross-sectional study. Data were extracted from the 2007 and 2013/14 ZDHS from the child’s file for women aged 15-49 years using a data extraction tool that was developed based on the questions asked in the questionnaire. Firstly, overall and provincial prevalence’s were estimated from the 2007 and 2013/14 data. Secondly, maps illustrating provincial variation of LBW prevalence were constructed and provincial statistical differences were assessed. Lastly, determinants of LBW were investigated. This involved descriptive statistics which included cross tabulations. Analytical statistics were done using bivariate logistic regression and to control for confounder multiple logistic regression was applied. A weighted analysis using STATA version 15.0 was used and level of significance was set at 5 percent. A total number of 8005 births within the five years preceding the survey were extracted as the study population. LBW prevalence remained stable between 2007 and 2013/14, at around 9 percent with no statistical difference. All provinces showed an increased prevalence except Central, Eastern, Lusaka, Northern and North-western. North-western was the only province that showed statistical difference. Mothers aged 20-34 years (AOR: 0.56 (0.44-0.71)) were 44 percent less likely to deliver LBW children than those aged below 20 years. Mothers aged 35-49 years (AOR: 0.53 (0.35-0.83)) were 47 percent less likely to deliver LBW children compared to mothers aged below 20 years. Compared to mothers who had not made any ANC visit, mothers who made 1-3 visits (AOR: 0.16 (0.04-0.62)) were 84 percent less likely to deliver a LBW child. Mothers who had made four or more visits (AOR: 0.14 (0.04-0.52)) were 86 percent less likely to deliver a LBW child compared to the mothers who did not make any ANC visit. The prevalence of LBW in Zambia remains high overall but showing sharp differential variation across the provinces in Zambia. This burden is concentrated in younger and predominantly rural mothers suggesting that there may be additional underlying inequity related to factors negatively associated with access or utilization of services. The study, therefore, recommends the need to have more programs that target such populations at risk including but not limited to programs against teenage pregnancies and strengthening the use of ANC services especially in provinces that showed an increased prevalence. Keywords: Low birthweight, Determinants, Antenatal care, Child survival, Neonatal mortality