Current information on the risk of uterine rupture after cesarean delivery has generally compared the risk after trial of labor to that occurring with an elective cesarean delivery without labor. Because antepartum counseling cannot account for whether a woman will develop an indication requiring a repeat cesarean delivery or whether labor will occur before scheduled cesarean delivery, the purpose of this analysis was to provide clinically useful information regarding the risks of uterine rupture and adverse perinatal outcome for women at term with a history of prior cesarean delivery.
Women with a term singleton gestation and prior cesarean delivery were studied over 4 years at 19 centers. For this analysis, outcomes from five groups were studied: trial of labor, elective repeat with no labor, elective repeat with labor (women presenting in early labor who subsequently underwent cesarean delivery), indicated repeat with labor, and indicated repeat without labor. All cases of uterine rupture were reviewed centrally to assure accuracy of diagnosis.
A total of 39,117 women were studied. In term pregnant women with a prior cesarean delivery, the overall risk for uterine rupture was 0.32% (125 of 39,117), and the overall risk for serious adverse perinatal outcome (stillbirth, hypoxic ischemic encephalopathy, neonatal death) was 106 of 39,049 (0.27%). The uterine rupture risk for indicated repeat cesarean delivery (labor or without labor) was 7 of 6,080 (0.12%); the risk for elective (no indication) repeat cesarean delivery (labor or without labor) was 4 of 17,714 (0.02%). Indicated repeat cesarean delivery increased the risk of uterine rupture by a factor of 5 (odds ratio 5.1, 95% confidence interval 1.49–17.44). In the absence of an indication, the presence of labor also increased the risk of uterine rupture (4 of 2,721 [0.15%] compared with 0 of 14,993, P<.01). The highest rate of uterine rupture occurred in women undergoing trial of labor (0.74%, 114 of 15,323).
At term, the risk of uterine rupture and adverse perinatal outcome for women with a singleton and prior cesarean delivery is low regardless of mode of delivery, occurring in 3 per 1,000 women. Maternal complications occurred in 3–8% of women within the five delivery groups.
Overall risk of uterine rupture at term with a prior cesarean delivery is 0.3% but ranges from 0% to 0.74%, depending on mode of delivery.
From the 1National Institute of Child Health and Human Development, Bethesda, Maryland; the 2Department of Obstetrics and Gynecology at the Ohio State University, Columbus, Ohio; the 3George Washington University Biostatistics Center, Washington, DC; the 4Departments of Obstetrics and Gynecology at the University of Alabama at Birmingham, Birmingham, Alabama; 5University of Texas Southwestern Medical Center, Dallas, Texas; 6University of Utah, Salt Lake City, Utah; 7University of Chicago, Chicago, Illinois; 8University of Pittsburgh, Pittsburgh, Pennsylvania; 9Wake Forest University, Winston-Salem, North Carolina; 10Thomas Jefferson University, Philadelphia, Pennsylvania; 11Wayne State University, Detroit, Michigan; 12University of Cincinnati, Cincinnati, Ohio; 12Columbia University, New York, New York; 13Brown University, Providence, Rhode Island; 14Northwestern University, Chicago, Illinois; 15University of Miami, Miami, Florida; 16University of Tennessee, Memphis, Tennessee; 17University of Texas at San Antonio, San Antonio, Texas; 18University of North Carolina, Chapel Hill, North Carolina; 19University of Texas at Houston, Houston, Texas; and 20Case Western Reserve University, Cleveland, Ohio.
* For members of the NICHD MFMU Network, see the Appendix.
Supported by grants from the National Institute of Child Health and Human Development (HD21410, HD21414, HD27860, HD27861, HD27869, HD27905, HD27915, HD27917, HD34116, HD34122, HD34136, HD34208, HD34210, HD40500, HD40485, HD40544, HD40545, HD40560, HD40512, and HD36801).
The authors thank Elizabeth Thom, PhD, for protocol/data management and statistical analysis, Francee Johnson, BSN, and Julia Gold, BSN/APN, for protocol development and coordination between clinical research centers, and Sandra Meadows for data management.
Corresponding author: Catherine Y. Spong, MD, Chief, PPB, NICHD, NIH, 6100 Executive Boulevard, Room 4B03 MSC 7510, Bethesda, MD 20892; e-mail: firstname.lastname@example.org.
Financial Disclosure The authors have no potential conflicts of interest to disclose.