The Excess Mortality Among Twins in the Dominican Republic and Haiti Through the Components of Age Under Five: A Comparative Study of Trends and Associated Factors

Despite the decline in mortality rates among children in developing countries, disparities persist between countries, particularly between twins and singletons. This study employed data from nine Demographic and Health Surveys in the Dominican Republic and Haiti to estimate and compare mortality rates for twins and singletons in categories of the under-5 age group (<i>neonatal, postneonatal,</i> and <i>child mortality</i>) and examine the factors associated with excess mortality among twins. From 1996 to 2013, the under-5 mortality rate (U5MR) for singletons in the Dominican Republic declined from 56‰ (95% CI [47, 64) to 30‰ (22-39) and from 108‰ (53-164) to 53‰ (16-89) among twins. In Haiti, between 1994 and 2016, the U5MR declined from 121‰ (109-133) to 77‰ (68-80) for singletons and from 432‰ (327-538) to 204‰ (149-260) among twins. The adjusted risk of neonatal death for twins is 1.4 (1.0-1.9) times higher than for singletons in the Dominican Republic, compared to a risk of 4.3 (3.5-5.3) times higher in Haiti. In the post-neonatal period, the mortality risk for twins in the Dominican Republic was 1.8 (1.0-3.1) times higher than that for singletons, 2.9 (2.3-3.8) in Haiti. The risk of death for twins was not significantly different from that for singletons in both the Dominican Republic and Haiti at ages 1-4 years. Low birth weight, lack of breastfeeding, absence of, or inadequate, antenatal care, noncesarean section birth, and high birth order were associated with excess mortality among twins in both countries.