Postneonatal and child mortality among twins in Southern and Eastern Africa

BACKGROUND: Few studies have evaluated the difference in mortality between twins and singleton children during the postneonatal and childhood period in sub-Saharan Africa. The aim of this study was to quantify the excess mortality of twins during the postneonatal and childhood period and to identify factors that contribute to the excess mortality among twins. The different use made of health care services was hypothesized to contribute to the increased mortality. METHODS: The Demographic and Health Survey data on Malawi, Tanzania and Zambia were pooled. Logistic regression was used to estimate twin/singleton differences for the combined postneonatal and child mortality and to study the role of intermediate factors and effect modifiers. RESULTS: The study was based on 18 214 singleton children and 706 twins. The twin/ singleton odds ratio (OR) of the combined postneonatal and child mortality was 2.33 (95% CI : 1.85-2.93). This excess mortality was largest during the first year of life. Control for intermediate factors (preventive health care and breastfeeding) did not sizeably diminish the mortality difference. Effect modifiers that were associated with increased twin/singleton OR were male sex, unwanted child, short birth interval and low socioeconomic status. CONCLUSIONS: The excess mortality of twins compared to singletons is considerable. A difference in use of preventive health care or in breastfeeding cannot explain the increased mortality. Males, unwanted children, those born after a short birth interval and the socioeconomically disadvantaged are at special risk. The generally good attendance at under-5 clinics gives health care providers the opportunity for increased surveillance of these high-risk groups.