Despite developments in prophylactic methods, venous thromboembolism (VTE) continues to be a serious complication following total joint arthroplasty. The new AAOS/ACCP guidelines on preventing pulmonary embolism (PE) after total hip/knee arthroplasty (THA/TKA) do not make specific recommendations for bilateral vs. unilateral procedures. In-patient PE rates were examined for patients undergoing unilateral or simultaneous bilateral TKA/THA at our institution in 2011. Of the 7,437 THA/TKA surgeries completed at our institution in 2011, 36 patients suffered from PE (0.48%). The rate of PE for unilateral TKA was 0.61% vs. 1.87% for bilateral (P < 0.001) and for unilateral THA was 0.17% vs. 0.52% for bilateral THA. Despite patients being screened before being cleared to undergo bilateral THA/TKA, they remain at higher risk for VTE. Copyright © 2014 Elsevier Inc. All rights reserved.