Trends in low-risk cesarean delivery in the United States, 1990-2013.

OBJECTIVES: This report describes trends in low-risk cesarean delivery rates in the United States from 1990 through 2013. Trends in low-risk cesarean delivery by state of residence, gestational age, age of mother, and race and Hispanic origin of mother are examined.
METHODS: Low-risk cesarean delivery is defined as a cesarean delivery among term (37 or more completed weeks), singleton, vertex (head first) births to women giving birth for the first time. Data for 1990-2012 are based on 100% of low-risk births to residents of all states and the District of Columbia. Data for 2013 are preliminary, and are based on nearly 100% of low-risk births in the United States.
RESULTS: The low-risk cesarean delivery rate reached a low of 18.4% in 1997 and then rose steadily to a high of 28.1% in 2009. The rate decreased from 2009 through 2013, reaching 26.9%. Declines were widespread during this time. Low-risk cesarean delivery rates were down for more than one-half of states. Rates declined for all term gestational ages (37 or more completed weeks); the largest decline was at 38 weeks, down 9%. Rates for all maternal age groups and race and Hispanic origin groups were also down. The largest declines were for women under 40 (6%-8%) and for non-Hispanic white women (6%); rates for these groups decreased at all term gestational ages. All material appearing in this report is in the public domain and may be reproduced or copied without permission; citation as to source, however, is appreciated.