Infections after fat grafting are very uncommon, but certainly not impossible. We perform the fat harvest, fat preparation and the transfer using strict sterile conditions. In addition, our patients routinely receive antibiotics for prevention just before the procedure and continue the drugs for a few days afterwards. Although we have never seen an infection after fat transfer, I would expect it to take about 7 days after the treatment before an infection could show. Increase in swelling, pain and redness are usual signs to look out for.