Adenomyosis among patients undergoing postpartum hysterectomy for uncontrollable uterine bleeding: A multicenter, observational, retrospective, cohort study on histologically-based prevalence and clinical characteristics.

OBJECTIVE:To assess the prevalence of adenomyosis at pathologic examination, and its association with obstetric complications, peripartum maternal clinical characteristics and neonatal birth weight in patients undergoing postpartum hysterectomy due to postpartum hemorrhage (PPH). METHODS:A multicenter, observational, retrospective, cohort study was carried out including all women who underwent postpartum hysterectomy due to PPH at gestational week 23+0 or later, between January 2010 and May 2023. Patients were categorized into two groups based on the presence of adenomyosis at pathologic examination, and were compared for obstetric complications, peripartum maternal clinical characteristics, and neonatal birth weight. RESULTS:The histologically-based prevalence of adenomyosis in patients undergoing postpartum hysterectomy due to PPH was 39.4%. Adenomyosis was associated with a longer hospitalization time (regression coefficient: 4.43 days, 95% CI: 0.34-8.52, P = 0.034) and a higher risk of hypertensive disorders (OR: 5.82, 95% CI: 1.38-24.46, P = 0.016), threatened preterm labor (OR: 3.34, 95% CI: 1.08-10.31, P = 0.036), urgent/emergency C-section (OR: 24.15, 95% CI: 2.60-223.96, P = 0.005), postpartum maternal complications (OR: 4.96, 95% CI: 1.48-16.67, P = 0.012), maternal intensive care unit admission (OR: 3.56, 95% CI: 1.05-12.05, P = 0.041), and low birth weight neonates (OR: 3.8, 95% CI: 1.32-11.02, P = 0.013). CONCLUSION:In patients undergoing postpartum hysterectomy due to PPH, adenomyosis is a highly prevalent condition among, and is associated with adverse obstetric, maternal, and neonatal outcomes.