Serra-Aracil X, et al. - In this observational study of consecutive patients undergoing transanal endoscopic microsurgery (TEM), researchers determined overall 30-day morbidity and relevant morbidity. In addition, they sought for risk factors for complications, rehospitalization, and the time of occurrence of the postoperative complications, as well as delineated the adverse effects following the hospitalization that the ambulatory or 1-day surgery (A-OdS) program would avoid. They identified 690 patients who underwent surgery; 639 of these were included in the study. They reported an overall morbidity rate of 151/639 patients (23.6%); the clinically relevant morbidity rate of 36/639 (5.6%) and mortality 2/639 (0.3%) were noted. Rectal bleeding was the most frequent complication reported; it was reported in 16.9% (108/639 patients); grade I in 86/108 patients (78. 9%). The first 2 days was identified to be the period with the greatest risk of complications. After 48 h, a rehospitalization rate of 7% was reported. Tumor size > 6 cm, anti-platelet medication, and surgeon’s experience < 150 procedures were the risk factors for complications.