OBJECTIVE: The purpose of this study was to estimate the association of uterine rupture and previous incision type, either unknown or low transverse, among women who attempt a trial of labor after 1 previous cesarean delivery.
STUDY DESIGN: We conducted a secondary analysis of a prospective multicenter observational study of 15,519 women with term singletons who attempted a trial of labor after 1 previous cesarean delivery. Odds ratios for the association between uterine incision location, either unknown or low transverse, and uterine rupture were estimated with the use of multivariable logistic regression.
RESULTS: Between 1999 and 2002, 99 of the 15,519 women (0.64%) who attempted a trial of labor after 1 previous cesarean delivery experienced a uterine rupture. Pregnant women with an unknown scar had lower odds of uterine rupture (adjusted odds ratio, 0.71; 95% confidence interval, 0.37-1.37) compared with women with a known low transverse scar. Other adverse maternal outcomes did not differ between the 2 groups of women.
CONCLUSION: Among this cohort, women with an unknown uterine incision who attempted a trial of labor were not at increased risk of uterine rupture compared with women with a known low transverse incision.
- trial of labor
- unknown scar
- uterine rupture
- vaginal birth after cesarean delivery
ASJC Scopus subject areas
- Obstetrics and Gynecology