Obstetric risk factors and outcome of pregnancies complicated with early postpartum hemorrhage: a population-based study.

OBJECTIVE: The study was aimed to identify obstetric risk factors for early postpartum hemorrhage (PPH) in singleton gestations and to evaluate pregnancy outcome. STUDY DESIGN: A comparison between consecutive singleton deliveries with and without early PPH was performed. Deliveries occurred during the years 1988-2002 in a tertiary medical center. A multivariate logistic regression model was constructed in order to define independent risk factors for PPH. RESULTS: Postpartum hemorrhage complicated 0.4% (n = 666) of all deliveries enrolled in the study (n = 154 311). Significant risk factors for PPH, identified using a multivariable analysis, were: retained placenta (OR 3.5, 95%CI 2.1-5.8), failure to progress during the second stage of labor (OR 3.4, 95%CI 2.4-4.7), placenta accreta (OR 3.3, 95%CI 1.7-6.4), lacerations (OR 2.4, 95%CI 2.0-2.8), instrumental delivery (OR 2.3, 95%CI 1.6-3.4), large for gestational age (LGA) newborn (OR 1.9, 95%CI 1.6-2.4), hypertensive disorders (OR 1.7, 95%CI 1.2-2.1), induction of labor (OR 1.4, 95%CI 1.1-1.7) and augmentation of labor with oxytocin (OR 1.4, 95%CI 1.2-1.7). Women were assigned into three different groups according to the assessed severity of PPH, assuming that the severe cases were handled by revision of the birth canal under anesthesia, and the most severe cases required in addition treatment with blood products. A significant linear association was found between the severity of bleeding and the following factors: vacuum extraction, oxytocin augmentation, hypertensive disorders as well as perinatal mortality, uterine rupture, peripartum hysterectomy and uterine or internal iliac artery ligation (p < 0.001 for all variables). CONCLUSION: Hypertensive disorder, failure to progress during the second stage of labor, oxytocin augmentation, vacuum extraction and LGA were found to be major risk factors for severe PPH. Special attention should be given after birth to hypertensive patients, and to patients who underwent induction of labor or instrumental delivery, as well as to those delivering LGA newborns.