L-3 A TRIAL OF LABOR AFTER CESAREAN DECISION ANALYSIS: THE IMPACT OF FUTURE PREGNANCIES

Tuesday, October 25, 2011: 1:30 PM
Columbus Hall C-F (Hyatt Regency Chicago)
(ESP) Applied Health Economics, Services, and Policy Research

Candidate for the Lee B. Lusted Student Prize Competition


Karla Solheim, MD1, Yvonne Cheng, MD, MPH2, Jeanne-Marie Guise, MD, MPH3, Yasser El-Sayed, MD4 and Aaron B. Caughey, MD, MPP, MPH, PhD3, (1)University of California, San Francisco, San Francisco, CA, (2)University of California, San Francisco, CA, (3)Oregon Health & Sciences University, Portland, OR, (4)Stanford University, Palo Alto, CA

Purpose: To analyze the decision for trial of labor after one prior cesarean compared with elective repeat cesarean, considering outcomes in future pregnancies in the analysis.                                                                                                                              

Method:  A decision analytic model was designed from the maternal perspective comparing elective repeat cesarean delivery (ERCD) and trial of labor after cesarean (TOLAC).  Baseline assumptions included a theoretical cohort of 300,000 women who had experienced only one prior pregnancy delivered via cesarean. Outcome probabilities were derived from the literature for major morbidities, including uterine rupture, maternal death, neonatal death, cerebral palsy, hysterectomy, and future placenta accreta. Costs and utilities taken from the literature were also applied to outcomes. Univariate and multivariate sensitivity analyses on key variables as well as a Monte Carlo simulation were performed for model validation.

Result:   ERCD was associated with more accretas ( 903 vs. 655) and more cesarean hysterectomies (2049 vs. 1602) but fewer uterine ruptures (2693 vs. 0) than TOLAC. Overall, TOLAC was the preferred strategy, resulting in 3,900 additional QALYs for the entire cohort.  A one-way sensitivity analysis found the risk of uterine rupture must reach 3.6% before performing an elective repeat cesarean becomes preferred. TOLAC was also cost-saving, costing $1380 less per delivery, for a total cost savings of $414M for the cohort. Even when the model was limited to the 2nd pregnancy, a trial of labor remained the dominant strategy, requiring a threshold of 2.7 % for uterine rupture before elective cesarean became the preferred option. Sensitivity analyses and a Monte Carlo simulation validated the robustness of the model over a broad range of inputs.

Conclusion: TOLAC leads to better outcomes on average than ERCD for women with one prior cesarean even without a history of prior vaginal births. The model's preference for TOL is magnified if future pregnancies are anticipated, given the potential morbidity of future placental abnormalities.  TOLAC is also cost saving. Table: Cost-effectiveness of TOLAC versus ERCD after one prior CD
Scenario Additional QALYs in TOLAC over ERCD Decreased cost in TOLAC over ERCD
All second pregnancies +3,900 -$414,000,000
No third pregnancy +2,700 -$248,000,000
Third pregnancy assumed +5,400 -$561,000,000