Prevalence trends of selected major birth defects: A multi-state population-based retrospective study, United States, 1999 to 2007

BACKGROUND We evaluated selected birth defects over a 9-year period to assess prevalence trends by selected maternal and infant factors. METHODS Data were pooled from 11 population-based birth defects surveillance programs in the United States for children born between 1999 and 2007. Overall prevalence, as well as 3-year interval prevalence, was calculated for 26 specific birth defects, stratified by maternal age, maternal race/ethnicity, and infant sex. Average annual percent change (AAPC) was calculated for each birth defect. Poisson regression was used to determine change in AAPC, and joinpoint regression to identify breakpoints and changes in slope for prevalence of each defect over time. RESULTS Between 1999 and 2001 and 2005 and 2007, four birth defects increased by 10% or more: coarctation of the aorta (17%), gastroschisis (83%), omphalocele (11%), and Down syndrome (10%). Among mothers