Consequences of Preterm Birth: Disparities among Hispanic Subgroups

Problem/Relevance: Health disparities among Hispanics are well documented.  However, when combined, important differences by Hispanic subgroups are masked.  Preterm birth rates (<37 weeks) in 2013 ranged from 10.9% among Puerto Ricans to 8.7% among Central/South Americans.  Not as well understood is how these disparities in prematurity impact infant mortality.

Methods:

National Center for Health Statistics (NCHS) 2010-2012 linked live birth/infant death files were analyzed to examine infant mortality rates (IMR) by maternal race/ethnicity, gestational age, and cause of death (using NCHS’ algorithm for preterm-related causes).

Results:

The IMR among whites and Hispanics was 5.1 per 1,000 live births.  Among Hispanics, Puerto Ricans had the highest IMR (7.2), followed by Mexicans (5.0), Cubans (4.4) and Central/South Americans (4.3). 

Among Hispanic infant deaths, 35.4% were due to preterm-related causes.  Despite a relatively low IMR and preterm birth rate (9.5% in 2012), half of Cuban infant deaths were preterm-related (50.2%).  Prematurity/low birthweight was the second leading cause of Hispanic neonatal death (22.8%), but was first among Puerto Ricans and Cubans on both neonatal death (28.5%; 25.9%, respectively) and infant death (IMR=145.5 per 100,000 live births; 90.3, respectively).  It was also the second leading cause of infant death among Hispanics overall (82.9).                          

Conclusions:

Infant mortality risk among Hispanic subgroups mirrors the ranking of preterm birth rates.  However, the contribution of preterm birth to infant mortality does not align with overall IMR, illustrating differential consequences of prematurity among subgroups and potentially identifying areas for concentrated efforts to reduce the burden of prematurity within Hispanic communities.