ANTENATAL ULTRASOUND PREDICTORS OF HEMORRHAGE, ANESTHETIC COMPLICATIONS, AND MATERNAL OUTCOMES DURING CESAREAN DELIVERY FOR PLACENTA PREVIA: A PROSPECTIVE COHORT STUDY

Abstract

Background: Placenta previa is associated with substantial perioperative hemorrhage, anesthetic complications, and maternal morbidity during cesarean delivery. Antenatal ultrasonography provides important information regarding placental morphology, cervical anatomy, and abnormal vascularity, potentially facilitating preoperative risk stratification and multidisciplinary management. Objective: To evaluate the associations of antenatal ultrasound markers with severe perioperative hemorrhage, anesthetic complications, and maternal outcomes among women undergoing cesarean delivery for placenta previa. Methods: This prospective, two-center cohort study included 100 women undergoing cesarean delivery for placenta previa between January 2025 and February 2026 at Sandeman Provincial Hospital, Quetta, and Lahore General Hospital, Lahore, Pakistan. Antenatal ultrasound assessment included cervical length, placental location and overlap, abnormal placental lacunae, loss of the retroplacental clear zone, and bridging vessels. Severe perioperative hemorrhage was defined as cumulative blood loss ≥1,500 mL during cesarean delivery and within 24 hours postpartum. Associations were evaluated using comparative statistical analyses and multivariable logistic regression. Results: Severe perioperative hemorrhage occurred in 32 women (32.0%), while 25 (25.0%) experienced clinically significant anesthetic complications. Cervical length ≤30 mm (adjusted odds ratio [aOR], 3.53; 95% confidence interval [CI], 1.33–9.41) and bridging vessels (aOR, 5.93; 95% CI, 2.17–16.21) were independently associated with severe hemorrhage. Bridging vessels were also significantly associated with anesthetic complications (aOR, 5.16; 95% CI, 1.85–14.37). Women experiencing severe hemorrhage had higher rates of blood transfusion, intensive care unit admission, and prolonged postoperative hospitalization. Conclusion: Short cervical length and bridging vessels were independently associated with severe perioperative hemorrhage in women with placenta previa, while bridging vessels were additionally associated with anesthetic complications. These findings support the potential clinical value of antenatal ultrasound markers in preoperative risk assessment and multidisciplinary delivery planning. Further validation in larger prospective cohorts is warranted.