The risk of developing outcomes will be compared between the intervention and control groups. Odds ratios and 95% confidence intervals (CI) will be calculated. Survival analysis will be done to assess survival rates in the sponge and control groups. The log rank test will be used to compare the survival rates between the two groups. Hazard ratios and 95% CI will be calculated for different variables using Cox regression analysis. Changes in QOL scores during the 5 year follow-up period will be compared between the sponge and control groups.