Seroma
Surgery leaves a potential space: after liposuction, the network of tunnels through the fat; after excisional surgery, the raw surface where tissue was lifted. The body responds to that injury by producing fluid, and where the fluid cannot drain or be reabsorbed fast enough it collects. That collection is a seroma.
It presents as a soft, sometimes fluctuant swelling, often appearing or worsening after the first week or two rather than immediately. It is usually not painful, though a large one can be uncomfortable and can distort the shape.
What raises the risk. Larger operations, extensive undermining of tissue, energy-assisted techniques in some surgeons' experience, abdominoplasty specifically, early return to activity, and poor compliance with compression.
How it is managed. Small collections are often left to reabsorb. Larger ones are drained with a needle, sometimes repeatedly over weeks, because they refill. Persistent seromas can develop a lining and become chronic, which occasionally requires surgical treatment.
Why it matters beyond inconvenience. A seroma can become infected, can delay healing, and can leave a lasting contour change once resolved. It is a reason to take compression and activity restrictions seriously rather than treating them as advisory, as set out at compression garments.
Haematoma
A haematoma is a collection of blood rather than serous fluid. It typically appears earlier than a seroma, sometimes within hours, and behaves differently.
It presents as rapid swelling, often on one side only, with increasing pain, tightness and sometimes discolouration. Unlike a seroma, it is usually uncomfortable and it usually announces itself.
What raises the risk. Bleeding that was not fully controlled, a rise in blood pressure after surgery, exertion or straining, vomiting, and medicines or supplements that affect clotting. This is one of the reasons you are asked about aspirin, anti-inflammatories, anticoagulants and herbal supplements before surgery, and why the answer needs to be complete.
How it is managed. Small ones may be observed. Larger or expanding ones usually need evacuation, which can mean a return to theatre. Gynaecomastia surgery carries a particular reputation for this, as noted at gynaecomastia surgery.
What you should do. Sudden asymmetric swelling with increasing pain is a same-day problem, not one to mention at the next appointment. Contact the provider immediately, and if you cannot reach them, seek medical attention.
Contour irregularity
Contour irregularity is uneven surface shape resulting from uneven removal of fat, or from uneven healing. It is the most common lasting disappointment in body contouring, and unlike the two above it is not a medical problem but an aesthetic one that is difficult to fix.
How it happens. Cannula passes that are not evenly distributed, working too superficially, using too large a cannula close to the skin, failing to feather the boundary of a treated area, or uneven healing in tissue that was already irregular. The technical detail is at cannulas and access.
What it looks like. Ridges corresponding to cannula tracks, localised dents or grooves, waviness across a treated area, a visible step where treatment stopped, or asymmetry between sides.
When to judge it. Not early. Early firmness and uneven swelling mimic contour irregularity closely, and a great deal that looks permanent at three months has resolved by twelve. Our page on when the result is final explains why.
What can be done. Options include further careful liposuction of surrounding areas to reduce contrast, fat grafting into a depression, and in some cases release of adherent skin. All are performed in scarred tissue, all are less predictable than a first operation, and none reliably restores what would have been. Realistic aims are improvement rather than correction.
What actually reduces the risk of each
Some of this is the surgeon's responsibility and some is yours.
Theirs. Careful haemostasis, appropriate use of drains, even cannula distribution, working in an appropriate plane, feathering boundaries, and not exceeding sensible operating time or volume.
Yours. Complete disclosure of medicines and supplements before surgery, strict adherence to compression, genuine activity restriction rather than a negotiated version of it, not returning to training early, and reporting problems when they appear rather than when they become undeniable.
The second list is the one people underestimate. A substantial proportion of seromas and haematomas follow a return to exertion at a point when the patient felt well.
Setting the expectation before surgery
These three complications are worth naming specifically in a consultation, because they are the ones you are most likely to meet.
Useful questions:
- How often do you drain a seroma after this operation, and is that included in the price?
- How often do you have to return someone to theatre for a haematoma?
- What does a contour irregularity look like on a body like mine, and what would you do about it?
- Is a revision for contour included, for how long, and who decides?
Note that all four questions are about what happens afterwards. A consultation that covers only the operation has covered the easy part. Our page on revision surgery deals with the rest.
Proportion
None of these three is a catastrophe. A seroma is drained. A haematoma is evacuated. A contour irregularity is lived with or partially improved. People recover from all of them and most go on to be satisfied with their result.
The reason to understand them in advance is that each of them is much less distressing when it was described to you beforehand than when it appears without warning and you are left interpreting it alone at three in the morning. Being told what is expected, what is a problem and who to call is the difference between an incident and a crisis.