To estimate the contributions of patient and health care provider–hospital characteristics to the variation in the frequency of nulliparous, term, singleton, vertex cesarean delivery in a multi-institutional U.S. cohort.
We performed a secondary analysis of the multicenter Assessment of Perinatal Excellence cohort of 115,502 mother and neonatal pairs who were delivered at 25 hospitals between March 2008 and February 2011. Women met inclusion criteria if they were nulliparous and delivered a singleton in vertex presentation at term. Hospital ranks for nulliparous, term, singleton, vertex cesarean delivery frequency were determined after risk adjustment. The fraction of variation in nulliparous, term, singleton, vertex cesarean delivery frequency attributable to patient and health care provider–hospital characteristics was assessed using hierarchical logistic regression.
Of the 115,502 deliveries in the initial cohort, 38,275 nulliparous, term, singleton, vertex deliveries met inclusion criteria. The median hospital nulliparous, term, singleton, vertex cesarean delivery frequency was 25.3% with a range from 15.0% to 35.2%. The majority of hospitals (16/25) changed rank quintiles after risk adjustment; overall the changes in rank were not statistically significant (P=.53). Patient characteristics accounted for 24% of the nulliparous, term, singleton, vertex cesarean delivery variation. The analyzed health care provider–hospital characteristics were not significantly associated with cesarean delivery frequency.
Although patient characteristics accounted for some of the variation in nulliparous, term, singleton, vertex cesarean delivery frequency and accounting for case mix had implications for hospital cesarean delivery rankings, the majority of the variation was not explained by the characteristics evaluated. These findings emphasize the importance of continued efforts to understand aspects of obstetric care, including case mix, that contribute to cesarean delivery variation.
Uncertainty regarding the factors that drive nulliparous, term, singleton, vertex cesarean delivery variation persists; however, case mix contributes meaningfully to low-risk cesarean delivery rates.
Departments of Obstetrics and Gynecology, University of Alabama at Birmingham, Birmingham, Alabama; Northwestern University, Chicago, Illinois; MetroHealth Medical Center–Case Western Reserve University, Cleveland, Ohio; Columbia University, New York, New York; the University of Utah Health Sciences Center, Salt Lake City, Utah; the University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; the University of Texas Southwestern Medical Center, Dallas, Texas; the University of Pittsburgh, Pittsburgh, Pennsylvania; The Ohio State University, Columbus, Ohio; the University of Texas Medical Branch, Galveston, Texas; Wayne State University, Detroit, Michigan; Brown University, Providence, Rhode Island; the University of Texas Health Science Center at Houston, McGovern Medical School–Children's Memorial Hermann Hospital, Houston, Texas; Oregon Health & Science University, Portland, Oregon; the George Washington University Biostatistics Center, Washington, DC; and the Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland.
Corresponding author: Daniel N. Pasko, MD, Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Alabama at Birmingham, 176F, 10270 619 19th Street South, Birmingham, AL 35249; email: firstname.lastname@example.org.
The project described was supported by grants from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (HD21410, HD27869, HD27915, HD27917, HD34116, HD34208, HD36801, HD40500, HD40512, HD40544, HD40545, HD40560, HD40485, HD53097, HD53118) and the National Center for Research Resources (UL1 RR024989; 5UL1 RR025764). Comments and views of the authors do not necessarily represent views of the National Institutes of Health.
Financial Disclosure The authors did not report any potential conflicts of interest.
Presented in part at the Society for Maternal-Fetal Medicine's 37th Annual Pregnancy Meeting, January 23–28, 2017, Las Vegas, Nevada.
See Appendix 1, available online at http://links.lww.com/AOG/B96, for a list of other members of the NICHD MFMU Network.
The authors thank Alan T. N. Tita, MD, PhD, for guidance in study design and manuscript preparation; Cynthia Milluzzi, RN, and Joan Moss, RNC, MSN, for protocol development and coordination between clinical research centers; and Elizabeth Thom, PhD, Madeline M. Rice, PhD, Brian M. Mercer, MD, and Catherine Y. Spong, MD, for protocol development and oversight.
Dr. Rouse, Associate Editor of Obstetrics & Gynecology, was not involved in the review or decision to publish this article.
Each author has indicated that he or she has met the journal's requirements for authorship.