Donor-site Seroma in Deep Inferior Epigastric Perforator Flap Breast Reconstruction: A Pooled Analysis.

BACKGROUND: Seroma at the abdominal donor site is a recognized complication following deep inferior epigastric perforator (DIEP) flap breast reconstruction. Reported incidences vary widely, reflecting differences in surgical technique, patient characteristics, and outcome reporting. Consequently, this proportional meta-analysis aims to estimate the pooled incidence of abdominal donor-site seroma and evaluate potential risk factors associated with its occurrence. METHODS: A systematic literature review of PubMed, Web of Science, and the Cochrane Library was performed up to June 2025. Studies reporting abdominal donor-site seroma rates following DIEP flap reconstruction were included. Data were pooled using a random-effects model (DerSimonian-Laird), and heterogeneity was assessed using I 2 and τ2 statistics. Univariable meta-regression analyses explored associations of smoking status and diabetes with seroma occurrence. RESULTS: The search identified 1345 unique records, of which 71 studies met the inclusion criteria, comprising 12,739 patients and 16,915 DIEP flaps. A total of 736 seromas were reported, yielding a pooled incidence of 6% (95% confidence interval, 4%-7%). Heterogeneity was substantial (I 2 = 85.3%, τ2 = 0.05, P < 0.001). The mean body mass index and age were 27.2 kg/m2 and 50.4 years, respectively. Meta-regression showed no significant association between seroma occurrence and smoking (P = 0.57) or diabetes (P = 0.07). CONCLUSIONS: Donor-site seroma occurs in 6% of DIEP flap reconstructions. The absence of associations with smoking or diabetes in meta-regression suggests that seroma formation may be influenced by technical and perioperative factors rather than by comorbidities.