The objective of this report is to review portal complications (PC) after pediatric liver transplantation (LT) for biliary atresia (BA) in the Bicêtre surgical series. From January 1, 1988, to February 28, 1995, 96 children with BA underwent 115 LTs Portal anastomosis was done on either the recipient portal vein (n = 85) or superior mesenteric vein (n = 11). No antiaggregative agents were administered postoperatively. Median follow-up was 50 months (range, 12 to 97). Nineteen PC (16.5%) occurred in 17 recipients: 16 portal thrombosis (PT) and 3 portal stenosis (PS). Fifteen instances of early PT occurred between days 0 and 17 (median, day 2). Emergency thrombectomy was performed in 9 cases (successful in 5). Three children underwent a secondary portosystemic shunt (successful in 2). Three PS were cured by either surgery or balloon dilatation. Four children died, 3 are alive with portal hypertension (PHT), and 10 are alive without PHT. Three-year patient actuarial survival is 82.4% in PC cases and 82% in others (NS). Significant risk factors of PC are young age and weight at the time of LT, small portal vein, and emergency LT. Analysis of our own results and review of the literature suggest that prevention of PC depends primarily on appropriate surgical technique. Reduction of postoperative hypercoagulability may also play an important role: a meta-analysis of 1,257 published pediatric LT show an overall risk of PT of 2.2% in teams using aspirin with or without dipyridamole compared with 7.8% when no antiaggregative agents are given (P = .0001).