Risk factors for blood transfusion during cesarean section in women with major placenta previa.

To identify risk factors for blood transfusion during cesarean section in women with major placenta previa. We conducted a retrospective single-center cohort study of 110 women with major placenta previa who underwent cesarean section at the Department of Obstetrics and Gynecology, Karlsruhe Municipal Hospital, between 2014 and 2021. We grouped patients by whether they received a perioperative blood transfusion. Maternal characteristics and clinical factors were compared to identify risk factors. Twenty women (18.2%) required a blood transfusion. No significant differences were observed between groups for maternal age, gestational age at delivery, elective versus urgent cesarean section, antepartum bleeding, use of assisted reproductive technology, or history of curettage. Prior cesarean section was associated with higher odds of perioperative transfusion (OR 4.63, 95% CI 1.65-12.95; Holm-adjusted p = 0.049). Major placenta previa itself is a recognized risk factor for obstetric hemorrhage and transfusion. Our study shows that a history of previous cesarean section is associated with an additional increase in transfusion risk. These findings emphasize the importance of careful preoperative planning and counseling in this high-risk population.