Who is a HIFU fibroid candidate?
HIFU suits a fibroid that causes symptoms you want treated, can be seen clearly on imaging and can be reached by the focused beam through the abdominal wall. It is aimed at women who want to keep the uterus and avoid an incision. HIFU treats the fibroid through the skin of the abdomen, without an incision. The uterus is not removed; HIFU treats the fibroid tissue and leaves the uterus in place.
Many fibroids need no treatment. ACOG notes that fibroids that cause no symptoms, are small, or occur in a woman nearing menopause often do not require it. Heavy or painful periods that cause anemia or disrupt daily life, bleeding between periods, pelvic pain and rapid growth are among the signs that may call for treatment (ACOG).
The scan comes first. Before treatment, the size, type and location of each fibroid are assessed by ultrasound to decide whether HIFU is suitable. The NHS describes the same step: an ultrasound shows whether you have fibroids, how many there are, where they are and how big they are (NHS). Doctors also weigh your symptoms, any scar on the abdominal wall, whether bowel lies in the path of the beam and whether you plan a pregnancy.
HIFU fibroid size limit and number of fibroids
Size and number matter because they set how much tissue has to be treated. In general, a larger fibroid, or several of them, means a longer session. The treatment session usually takes one to two hours. That is a typical session, not a promise for every case. Results and recovery vary from person to person.
Published protocols use similar limits. A two-center European study of ultrasound-guided HIFU in Germany and Bulgaria accepted fibroids up to 12 cm. It also required a safe acoustic path to the fibroid and no more than 11 cm from the skin to the deepest part of the tumor, with the patient lying face down (Dohmen et al., 2025). Those are one study's entry rules, not a statement of what any other clinic requires.
Fibroid types and where they sit
Doctors describe fibroids by where they grow: inside the cavity of the uterus (submucosal), within the muscle wall (intramural), on the outer surface of the uterus (subserosal), or on a stalk (pedunculated). The international FIGO system numbers these positions from 0 to 8. Position affects both the symptoms a fibroid causes and which treatments can reach it.
A fibroid attached to the uterus by a stem can twist, which may cause pain, nausea or fever (ACOG). A fibroid that protrudes into the cavity of the uterus can be removed through the cervix with a hysteroscope (ACOG).
Fibroids that are not treated with HIFU
Subserosal fibroids that project outward from the surface of the uterus (pedunculated subserosal fibroids) are not treated with HIFU. A 2024 review of fibroid treatments lists pedunculated subserosal fibroids as unsuitable for embolization, MR-guided focused ultrasound and radiofrequency ablation, because the risk of necrosis with expulsion is high (Micić et al., 2024). The European study above excluded them as well. A fibroid on a stalk can also lie against the bowel and other organs that the heat must not reach.
Other findings usually count against HIFU. The same European protocol excluded fibroids with severe calcification or hyaline degeneration, fibroids that could not be seen well enough on ultrasound (for example because of extensive scarring in the beam path), suspected cancer of the uterus, pregnancy and acute inflammation (Dohmen et al., 2025). ACOG notes that fibroids can rarely be associated with cancer, and lists rapid growth and uncertainty about what a growth is among the signs that may signal the need for treatment.
Scars, wall thickness and MRI findings that change the odds
Some features do not rule HIFU out but raise the risk or lower the chance of a lasting result. In a Chinese study that compared 123 women with thermal injury of the abdominal skin with 246 women without it, abdominal scars, a thicker abdominal wall, fibroids in the upper part of the uterus (the fundus) and fibroids that looked bright or mixed on T2-weighted MRI were each linked to injury, as were higher power and longer treatment time (Chendian et al., 2024). A UK series reported a second-degree skin burn in a patient with a cesarean scar (Lyon et al., 2019). Tell the doctor about any abdominal scar.
Brightness on MRI also relates to results. A meta-analysis of 18 studies found that reintervention was 3.45 times more likely for fibroids that were bright (hyperintense) on T2-weighted images than for fibroids that were dark or similar to muscle (Dou et al., 2024). If you already have an MRI report, send it with your ultrasound.
When another option may suit you better
Another treatment may fit better if the fibroids are larger than about 12 cm, if there are more than 12 of them, if a fibroid projects outward from the surface of the uterus, or if the beam path is blocked. A fibroid that protrudes into the cavity may be better removed through the cervix.
Plans for a pregnancy matter too. NICE guidance on MR-guided focused ultrasound says the effects on fertility and pregnancy are uncertain. A 2025 meta-analysis found lower pregnancy and live birth rates after HIFU than after myomectomy, and its authors noted the limited quality of the studies (Chen et al.).
Fibroid treatment options other than HIFU are compared in detail elsewhere on this site, including how each one affects plans for a pregnancy.
What to send before you travel
Useful records are a recent ultrasound or MRI report with measurements, a list of your symptoms and when they began, any earlier treatment, and a note of any abdominal surgery or scar. Consultations are available in English.
If a consultation in Seoul looks likely, the practical steps are how to book, what to bring and whether you need a visa. This page is general information and is not a diagnosis; a consultation is needed to decide whether a procedure suits you.
Questions
Am I a HIFU fibroid candidate if I have several fibroids?
Possibly. HIFU is offered for fibroids up to about 12 cm in size and up to 12 fibroids in number. More fibroids usually mean a longer session, and each one has to be reachable by the beam, so the scan decides.
Can I have HIFU if I want to get pregnant?
Many women who struggled to conceive because of fibroids are able to get pregnant after treatment (ACOG), but the evidence after HIFU is limited. NICE guidance on MR-guided focused ultrasound says the effects on fertility and pregnancy are uncertain, and a 2025 meta-analysis found lower pregnancy and live birth rates after HIFU than after myomectomy while noting the limited quality of the studies (Chen et al.). Tell the doctor early if you plan a pregnancy.
Does a cesarean scar rule out HIFU?
Not automatically. A scar in the beam path raises the risk of a skin burn, so the doctor needs to know about it and weigh it against your scan (Chendian et al., 2024; Lyon et al., 2019). Tell the doctor about any abdominal surgery, however long ago.
Do I need an MRI before HIFU?
Before treatment, the size, type and location of each fibroid are assessed by ultrasound to decide whether HIFU is suitable. If you already have an MRI report, send it with your ultrasound. MRI shows how bright a fibroid looks on T2-weighted images, and in studies bright fibroids were more likely to need further treatment (Dou et al., 2024).
Sources
- ACOG patient FAQ: Uterine fibroids
- NHS: Fibroids
- NICE HealthTech guidance HTG277 (formerly IPG413): MR-guided focused ultrasound for uterine fibroids, recommendations
- Dohmen et al., 2025: ultrasound-guided HIFU for fibroids at two European centers, European Radiology (PubMed)
- Micić et al., 2024: currently available treatment modalities for uterine fibroids, Medicina (PubMed)
- Chendian et al., 2024: factors linked to abdominal skin injury in ultrasound-guided focused ultrasound ablation of fibroids (PubMed)
- Lyon et al., 2019: ultrasound-guided HIFU for fibroids, Ultraschall in der Medizin (PubMed)
- Dou et al., 2024: reintervention after HIFU for fibroids, meta-analysis (PubMed)
- Chen et al., 2025: reproductive outcomes of HIFU and myomectomy for fibroids, meta-analysis (PubMed)
About the reviewer
Dr. Mo Hyung-jin, MD, PhD, board-certified OB-GYN specialist, is the medical director of Podo Women's Clinic. He developed the pelvic ligament suspension technique used at the clinic for stress urinary incontinence and pelvic organ prolapse. Profile