Just over one in five live, singleton births in 2012 were delivered by cesarean section for first-time mothers, showing slight declines in the rates since 2009 among the U.S. states included in a recent report.
The overall primary cesarean delivery rate was 21.5% for the 38 states – plus the District of Columbia and New York City – that had implemented the 2003 U.S. Standard Certificate of Live Birth (revised) by, at latest, Jan. 1, 2012, according to a National Vital Statistics Report from the National Center for Health Statistics.
State-specific rates in 2012 ranged from a low of 12.5% in Utah to a high of 26.9% in Florida and Louisiana, the investigators reported Jan. 23 (Natl. Vital Stat. Rep. 2014;63:1-10).
The report did not include any data from states that used the 1989 U.S. Standard Certificate of Live Birth (unrevised) through 2012 since the 1989 certificate reports on the "method of delivery" differently than the 2003 revised certificate. The data are, therefore, not generalizable to the entire country since the births are not a random sample or representative of the national demographics, especially in terms of Hispanics’ distribution.
Instead, the report’s data are presented based on when states implemented the revised 2003 certificate, a process that occurred gradually over about a decade. Among the 19 states (excluding New York City) that had implemented the 2003 certificate by Jan. 1, 2006, the primary cesarean rate first increased from 21.9% in 2006 to 22.4% in 2009 and then dropped to 21.9% in 2012. The lower rate in 2012 resulted from declines in 11 of the 19 states since 2009 while the other eight states had no significant changes in their rates.
The 28 states plus New York City that implemented the 2003 certificate by Jan. 1, 2009, also showed a decline from 2009, when the primary cesarean rate was 22.1%, to 2012, when the rate was 21.5%. This overall decline resulted from decreases in the cesarean rates in 16 of the 29 total areas included, while the other 13 areas’ rates did not significantly change. Utah’s rate during this time dropped 15%, while Delaware, New York, New York City, North Dakota, and Oregon saw drops of 5% to 10% from 2009 to 2012.
"Although significant declines were observed for total 2006 and 2009 revised reporting area rates and for many state-specific rates between 2009 and 2012, the pace of the decline has slowed," the authors wrote. For example, only two of the 19 states using the revised certificate by 2006 saw declines from 2011 to 2012, even though 13 states from this group saw declines from 2009 to 2010.
Few changes occurred in cesarean rates based on gestational age at the state level, with the only statistically significant change across multiple states occurring among babies born at 38 weeks. Among 18 of the 29 areas that adopted the 2003 certificate by 2009, the rate for this gestational age dropped an average of 10% from 2009 to 2012.
The decline varied from a 5% drop in Michigan to an 18% drop in Utah. States seeing a drop of at least 10% in primary cesarean rates at 38 weeks for those years included Georgia, Kansas, Nebraska, New Mexico, New York, New York City, Ohio, Oregon, Utah, and Washington. The overall primary cesarean rates for all 29 areas combined did show decreases for each gestational age from 37 weeks to 41 weeks and for 42 or more weeks.
The report was funded by the National Center for Health Statistics. No disclosures were reported.