In the recent article by Dr Vergani et al, we read with interest the information presented regarding placental distance from the cervical os and mode of delivery. However, we had numerous concerns with the data presented in the study.

The prevalence of “prelabor” cesarean section deliveries that were performed in the study was high. This, in turn, revealed a small sample size of patients with a placenta previa who had a trial of labor (TOL). In addition, the study did not actually reveal how many patients had a TOL. Based on the information provided, we were able to deduce that there were likely 6 patients with a placenta 1–10 mm (group 1) from the os and 20 patients with a placenta 11–20 mm (group 2) from the cervical os who would have had a TOL. It would be beneficial if the authors could confirm theses numbers. Outcomes for those patients who actually had a TOL are, in our opinion, of most clinical relevance. If the authors would provide these data, it may indicate some initial evidence to suggest whether patients with a placenta previa and TOL had reasonable outcomes.

Interestingly, of the data that were presented, estimated blood loss (EBL) for group 1 and group 2 was similar. Given that group 2 had fewer cesarean section deliveries, we would have expected group 2 to have significantly less EBL. This may have been influenced by placenta position, because it was noted there were more anterior placentas in group 2 than in group 1 (48% vs 29%), and it is expected that cesarean deliveries with an anterior placenta will have a higher EBL. It would be valuable to know which patients (TOL vs cesarean delivery) had an anterior placenta. If there is no evidence of higher EBL for those with a cesarean delivery and anterior placenta, then, alternatively, it may indicate that a higher than average EBL occurred for the patients with a TOL, which would be an outcome of concern.

This study presented a number of patients who had a vaginal delivery with a placenta previa. Unfortunately, the necessary data for those who had a TOL were not presented, thereby limiting clinical application. However, this study provides evidence that there may be clinical equipoise to justify future studies.