Parto vaginal después de una cesárea previa, hospital san juan de dios, cali (colombia). estudio de cohorte

Objective: determining the incidence of vaginal birth following a prior cesarean section and evaluating the predictive ability of the vaginal birth predictor score on the admission scoring system described by Flamm in 1997. Materials and methods: this was a retrospective cohort study of women having undergone a prior cesarean section and then a pregnancy lasting at least 37 weeks who had consulted at the San Juan de Dios hospital in Cali (HSJD) between May 30th 2007 and May30th 2008. The vaginal birth rate was calculated and sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were evaluated, as were positive (RVP) and negative verisimilitude ratios (RVN) regarding vaginal birth predictor score following a cesarean when their scores were 4 or more and 8 or more. Results: there were 20.3% vaginal births in this group; 36% of the pregnant women having scores between 4 and 7 had undergone vaginal birth and 83% of the expectant mothers scoring 8 or more. A ≥4 points cut-off point gave 85.7% sensitivity, 69.1% specificity, 41.3% Positive Predictive Value (PPV) and 95% Negative Predictive Value (NPV) and 2.8 Positive likelihood ratio P LR(+) and 0.2 Negative likelihood ratio (NLR). If cut-off point were ≥8, then this gave 83.3% sensitivity, 82.6% specificity, 17.9% PPV, 99.1% NPV, 4.8 RVP and 0.2 RVN. Conclusion: vaginal birth frequency following a cesarean section was 20%. Pregnant women having scores less than 4 had a low probability of having a vaginal birth.