Implant-based breast reconstruction is a common plastic surgery procedure with well-documented clinical outcomes. Despite this, the natural history and timing of key complication endpoints are not well described. The goal of this study is to determine when patients are most likely to experience specific adverse events after implant-based reconstruction.

Retrospective consecutive series of patients who received mastectomy and implant-based reconstruction over a 6-year period were included. Complications and unfavorable outcomes including hematoma, seroma, wound infection, skin flap necrosis, capsular contracture, implant rippling, and implant loss were identified. A time-to-event analysis was performed and Cox regression models identified patient and treatment characteristics associated with each outcome.

Of 1473 patients and 2434 total reconstructed breasts, 785 complications/unfavorable outcomes were identified. The 12-month cumulative incidence of hematoma was 1.4%, seroma: 4.3%, infection: 3.2%, skin flap necrosis: 3.9%, capsular contracture: 5.7%, implant rippling: 7.1%, and implant loss: 3.9%. In the analysis, 332/785 (42.3%) complications occurred within 60 days of surgery; 94% of hematomas, 85% of skin necrosis events, and 75% of seromas occurred during this period. Half of all infections and implant losses also occurred within 60 days. Of the remaining complications, 94% of capsular contractures and 93% of implant rippling occurred >60 days from surgery.

Complications following mastectomy and implant-based reconstruction exhibit a discrete temporal distribution. These data represent the first comprehensive study of the timing of adverse events following implant-based reconstruction. These findings are immediately useful to guide postoperative care, follow-up, and clinical trial design.