After pelvic fat grafting, shape-related problems emerge over the months while swelling resolves, whereas inflammation or bleeding can appear in the early postoperative period. Hard lumps, an uneven contour and left-right volume differences sit close to normal recovery responses, so clear criteria are needed to tell them apart. How much volume remains and whether both sides stay even also come back to take rate.
Contents
What forms do complications take?
The American Society of Plastic Surgeons lists asymmetry, fat necrosis, fluid collection, infection and prolonged swelling among the risks of buttock surgery.
Complications of pelvic fat grafting divide into shape problems — asymmetry, irregularity, more volume loss than expected — and tissue problems such as lumps, inflammation and fluid collection.
In a safety review of fat grafting to the breast and gluteal regions, most complications were fat necrosis, and they increased with larger graft volumes.[1]
How are recovery responses and complications told apart?
Read the direction of change, the severity of symptoms and the timing together. Gradual improvement points to recovery; heat or severe pain calls for immediate assessment.
| Sign | Common recovery response | Warrants assessment |
|---|---|---|
| Swelling | Both sides swollen, settling gradually | One side enlarging or fluctuating |
| Pain | Less each day | Worsening, with heat |
| Firmness | Softening slowly | A well-defined lump that does not shrink |
| Shape | Asymmetry from swelling | Asymmetry persisting after swelling resolves |
Swelling takes roughly three to six months to subside and volume to stabilise, so the final shape is assessed with the clinical team after that.
In an analysis of outpatient fat grafting complications, infection accounted for 22.3% of buttock fat grafting complications — heat, redness and increasing pain should be checked immediately.[2]
Why do lumps and irregular contours form?
Transferred tissue has no blood supply at first and draws nutrients from its surroundings. Where a large amount is concentrated in one place, blood cannot reach the centre and necrosis can follow, leaving a hard lump or firm area.
Contour irregularity appears when fat is not distributed evenly or when only some of it is absorbed, creating differences in height. How the tissue is divided as well as how much is placed affects the outcome.
Why does take rate decide the result?
Take is the process by which grafted tissue builds new vessels and settles; some is absorbed, so the immediate postoperative volume is not what remains. A low take rate means less volume than expected, and if absorption clusters on one side it can lead to asymmetry.
Read alsoDesigning buttock fat grafting is covered in “Buttock fat grafting: can the waist look narrower and the pelvis wider?” (Korean).
Which changes need a clinic visit?
If any of the following appear, have them checked at the operating clinic:
- Redness and heat
- Pain that does not settle and worsens
- One side suddenly swelling or fluctuating
- Discharge from a wound
- New or growing lumps, or lumps that do not shrink
Sudden breathlessness, chest pain or altered consciousness may indicate an emergency such as fat embolism and requires the emergency department immediately.
Pelvic fat grafting: common myths and facts
| You may think… | In practice |
|---|---|
| "Swelling and complications cannot be told apart." | Heat, one-sided pain, pus are complication signs. |
| "All lumps resolve with time." | Lumps from fat necrosis may remain. |
| "More fat means better take." | Over-injection increases fat necrosis. |
In recovery consultations I ask patients to compare the two sides. Swelling usually subsides on both similarly; if one side alone is red, hot or increasingly painful, it needs to be seen.
Pelvic fat grafting problems split into shape and tissue: shape issues surface as swelling resolves over three to six months, while inflammation or bleeding can appear early. Most complications in a safety review were fat necrosis, increasing with larger graft volumes, and infection made up 22.3% of buttock fat grafting complications in an outpatient analysis — so heat, worsening pain and discharge are checked regardless of timing. Sudden breathlessness or chest pain is an emergency, not a recovery variant.
🔬 The research behind this article
These are the international journal papers that support the content above. Select a title to open the abstract on PubMed.
- Plastic and Reconstructive Surgery 2019 — safety review of fat grafting to breast and gluteal regionsChopan M, White JA, Sayadi LR, Buchanan PJ, Katz AJ. Autogenous Fat Grafting to the Breast and Gluteal Regions: Safety Profile Including Risks and Complications. Plast Reconstr Surg. 2019;143(6):1625-1632.Key: mostly fat necrosis, more frequent with large volumesText [1] · PMID 31136476 · DOI
- Aesthetic Surgery Journal 2024 — analysis of outpatient fat grafting complicationsWeidman AA, Foppiani J, Valentine L, et al. Complications From Fat Grafting and Gluteal Augmentation in Outpatient Plastic Surgery: An Analysis of American Association for Accreditation of Ambulatory Surgery Facilities (AAAASF, QUAD A) Data. Aesthet Surg J. 2024;44(7):722-730.Key: infection 22.3% of buttock fat grafting complicationsText [2] · PMID 37996070 · DOI
🎬 Watch: Dr. Park Seong-Soo on video
Korean-language videos from BongBong Plastic Surgery's official channel and Dr. Park's channel, “Seongsu-ro Doctor”. Titles are translated for reference; selecting one opens YouTube.
- Is more fat always better? How BiVol improves hip-up graft survivalSeongsu-ro Doctor · 2026.08.28
- How to fill a slim hip: hip dip volume and firmness with BiVolSeongsu-ro Doctor · 2025.12.22
Frequently asked questions
Is a hard grafted area always a complication?
A. Firmness across the whole grafted area early on is a common recovery response. A new or growing well-defined lump with pain or skin change should be checked promptly.
What should I observe during recovery?
A. Change position often so the grafted area is not pressed for long periods, and avoid smoking, heavy drinking and rapid dieting.
Can asymmetry left after swelling resolves be corrected?
A. Asymmetry or irregularity persisting after stabilisation can be planned for correction by topping up or tidying. Shape is assessed after swelling settles, while heat, worsening pain and discharge are checked immediately.
📖 References
Select a [number] in the text to jump to the source, and ↩ to return. Only papers whose title, journal and year were verified on PubMed are included.
- Chopan M, White JA, Sayadi LR, Buchanan PJ, Katz AJ. Autogenous Fat Grafting to the Breast and Gluteal Regions: Safety Profile Including Risks and Complications. Plast Reconstr Surg. 2019;143(6):1625-1632. — Plastic and Reconstructive Surgery 2019 — safety review of fat grafting to breast and gluteal regions. ↩
- Weidman AA, Foppiani J, Valentine L, et al. Complications From Fat Grafting and Gluteal Augmentation in Outpatient Plastic Surgery: An Analysis of American Association for Accreditation of Ambulatory Surgery Facilities (AAAASF, QUAD A) Data. Aesthet Surg J. 2024;44(7):722-730. — Aesthetic Surgery Journal 2024 — analysis of outpatient fat grafting complications. ↩
BongBong Plastic Surgery · Dr. Park Seong-Soo, Medical Director
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