Objective. Inguinofemoral lymphadenectomy for patients with vulvar squamous cell carcinoma is associated with a high incidence of postoperative wound complications, which may be influenced by inguinal drain management. The aim of this nationwide prospective study (MAMBO: Morbidity And Measurement of the BOdy) was to assess the feasibility and the incidence of complications after volume-controlled versus short drainage. Methods. The MAMBO study consisted of two observational studies in all eight oncology centers in the Netherlands, conducted between 2012 and 2016. In the first study, the drain was removed when the production was Results. We included 77 patients (139 groins) for volume-controlled drainage and 64 patients (112 groins) for short drainage. Volume-controlled drainage was associated with significant less lymphocele formation. Moreover, we found no difference in wound infection or primary wound breakdown. The estimated incidence of one or more complications was 46% per groin after volume-controlled drainage versus 75% after short drainage, (RD 29% (95% CI 8, 49) p = 0.006). Conclusions. This prospective study shows that volume-controlled drainage is associated with significantly less complications compared to short drainage. We therefore recommend volume-controlled drainage after inguinofemoral lymphadenectomy in patients with vulvar squamous cell carcinoma.