How to boost an obstetrician's confidence in vaginal delivery after high-intensity focused ultrasound: a comparison study on delivery outcomes

Abstract

Objective: To assess the feasibility of vaginal delivery after HIFU. Methods: A total of 37 women who met the trial of labor after HIFU (TOLAH) inclusion criteria and 368 women who met the trial of labor after cesarean delivery (TOLAC) inclusion criteria gave birth at Shanghai First Maternity and Infant Hospital between 14th June 2018 and 24th September 2021. The delivery outcomes of the two groups were compared. Multivariable logistic regression analysis was used to estimate the adjusted risk of postpartum hemorrhage (PPH). Results: In the Qualified Candidates for TOLAH group, vaginal delivery is substantially less common (p = 0.000). The prevalence of PPH in the Qualified Candidates for TOLAH group is lower than in the Candidates for TOLAC group (8.82% vs 10.51%, p = 0.534; 0% vs 2.51%, p = 0.418). Hemoglobin drop in the Qualified Candidates for TOLAH group is also lower (7.03 ± 7.39vs 12.11 ± 12.62, p = 0.001). The rate of using more than two types of uterotonic medications to promote contraction is significantly lower in the Qualified Candidates for TOLAH group (54.05% vs 69.84%, p = 0.04), and the percentage of abnormal uterine contraction is lower in the Qualified Candidates for TOLAH group (35.14% vs 49.18%, p = 0.072). PPH is strongly predicted by abnormal uterine contraction (aOR: 17.177, 95% CI:5.046 ∼ 58.472, p = 0.000), but not by HIFU (aOR:1.105; 95% CI:0.240 ∼ 5.087, p = 0.898). No uterine rupture occurred in the cases after HIFU. Conclusions: No uterine rupture occurred in our study group after HIFU. HIFU is not a risk for PPH. It is promising for those after HIFU to choose vaginal delivery.