A fundal fibroid is a noncancerous growth located in the fundus, the uppermost part of the uterus. The fundus is the broad, dome-shaped region where the fallopian tubes connect. About 14 to 24% of uterine fibroids develop in this area, making it the second most common location after the main body (corpus) of the uterus.
Like all uterine fibroids, a fundal fibroid is made of muscle and connective tissue. What sets it apart is simply where it sits. That location influences which symptoms you experience, how it affects pregnancy, and which treatment approaches work best.
Where the Fundus Is and Why Location Matters
The uterus has four segments stacked from top to bottom: the fundus, corpus, isthmus, and cervix. The fundus is the highest point, curving above the openings of both fallopian tubes. Because it forms the “ceiling” of the uterine cavity, a fibroid growing here can press upward into the abdomen or inward toward the space where a pregnancy would implant.
A fundal fibroid can grow in any of the three standard fibroid positions. An intramural fundal fibroid sits within the muscular wall itself. A submucosal fundal fibroid bulges inward, distorting the uterine cavity. A subserosal fundal fibroid grows outward from the uterine surface. Some hang from a stalk, called a pedunculated fibroid. The depth of the fibroid within the wall matters as much as its address in the fundus, because fibroids that press into the cavity tend to cause the most bleeding and fertility problems.
Common Symptoms
Many fundal fibroids cause no symptoms at all, especially when they’re small. When they do cause problems, the symptoms overlap with fibroids in other locations but can have a few distinctive patterns because of the fundus’s position at the top of the uterus.
Heavy menstrual bleeding is the most common complaint, affecting roughly 30% of people with uterine fibroids. Fibroids trigger this by disrupting blood vessel formation in the surrounding tissue. The network of blood vessels that develops around a fibroid is structurally fragile and prone to leaking. Fibroids can also physically compress veins in the uterine lining, creating pools of blood that contribute to heavier flow.
Because the fundus sits high in the pelvis, a large fundal fibroid tends to push upward into the abdominal cavity rather than downward toward the bladder or rectum. This can cause visible abdominal enlargement, sometimes making the abdomen look pregnant. Other possible symptoms include:
- Back pain or a sense of pelvic pressure
- Frequent urination or difficulty fully emptying the bladder, if the fibroid is large enough to press on nearby structures
- Constipation or rectal pressure
- Pain during sex
How Fundal Fibroids Affect Fertility
The fundus is one of the preferred implantation sites for a fertilized embryo, so a fibroid here can interfere with conception depending on its type. The clearest evidence comes from assisted reproduction research.
Submucosal fibroids that distort the uterine cavity have the most dramatic effect. Compared to women without fibroids, those with submucosal fibroids have about a 70% lower chance of pregnancy and implantation through fertility treatment. They also have notably higher rates of miscarriage and lower rates of live births.
Intramural fibroids (the type embedded in the muscle wall) have a more moderate impact. Implantation rates drop by about 38%, and delivery rates fall by roughly 30% per treatment cycle. Subserosal fibroids, which grow outward, have negligible effects on fertility.
This means that a fundal fibroid’s effect on your ability to conceive depends heavily on whether it’s pushing into the uterine cavity or growing away from it. A small subserosal fundal fibroid is unlikely to affect pregnancy, while even a modest submucosal one at the same location could be significant.
Risks During Pregnancy
A 2024 meta-analysis confirmed that uterine fibroids raise the risk of several pregnancy complications, including preterm birth, cesarean delivery, placenta previa (where the placenta covers the cervix), placental abruption, postpartum hemorrhage, breech presentation, and preeclampsia. Larger fibroids were specifically linked to higher rates of breech presentation, postpartum hemorrhage, and placenta previa compared to smaller ones.
A fundal fibroid can be particularly relevant for fetal positioning. Because the fundus is where the baby’s buttocks typically rest in a head-down position, a large fibroid there may crowd the space and contribute to breech or other abnormal positions. This is one reason fibroids in the fundus are closely monitored during pregnancy.
How It’s Diagnosed
Most fundal fibroids are first spotted on a transvaginal ultrasound, often during a routine exam or when you report symptoms like heavy bleeding. Ultrasound can identify the fibroid’s size and general location, but it has limits when distinguishing exactly how deep a fibroid sits within the wall.
MRI provides a more detailed picture. It can precisely show whether the fibroid distorts the uterine cavity (submucosal), stays within the wall (intramural), or protrudes outward (subserosal, defined as more than 50% of its volume pushing beyond the outer surface). This distinction matters because it guides treatment decisions, especially if fertility is a concern.
Treatment Options
Treatment depends on your symptoms, the fibroid’s size and type, and whether you want to preserve fertility. Not every fundal fibroid needs treatment. Small, symptom-free fibroids are typically monitored with periodic imaging.
Medications
Medications are generally used for short-term symptom control rather than as a permanent fix. Hormonal options can reduce bleeding and, in some cases, shrink fibroids. One class of drugs works by blocking the effects of progesterone on fibroid cells, which triggers cell death and reduces the surrounding tissue. These medications have been shown to shrink fibroid volume by 17 to 57% and can keep fibroids from regrowing for up to six months after stopping treatment. Unlike some other hormonal therapies, they don’t affect bone density, which makes them suitable for longer intermittent use.
Other hormonal approaches work by temporarily shutting down estrogen production. These tend to cause menopause-like side effects and are usually limited to a few months, often used to shrink a fibroid before surgery.
Surgical Removal
Myomectomy removes the fibroid while preserving the uterus. It can be done through several approaches: laparoscopy (small incisions with a camera), laparotomy (a larger abdominal incision), or hysteroscopy (through the vagina and cervix, for fibroids that protrude into the cavity). The approach depends on the fibroid’s size, number, and depth within the wall.
For women who plan to become pregnant after a fundal myomectomy, the risk of uterine rupture during a future pregnancy is a common concern. A systematic review found the overall rate was about 0.5 to 0.9%, and in one case series, none of the ruptures occurred during labor itself. Your care team will typically recommend a waiting period before conception and may advise a planned cesarean delivery depending on how deep the surgical repair went.
Hysterectomy, the removal of the entire uterus, is considered a definitive option for women who don’t want future pregnancies and have severe symptoms.
Minimally Invasive Procedures
Several newer options fall between medication and major surgery. Uterine artery embolization cuts off blood flow to the fibroid, causing it to shrink. MRI-guided focused ultrasound uses heat to destroy fibroid tissue without incisions. Radiofrequency ablation uses targeted energy to shrink fibroids. All three are associated with good symptom relief, though they aren’t recommended for submucosal fibroids or pedunculated fibroids because of a higher risk of tissue breakdown and complications.
The right choice depends on a combination of factors: how much the fibroid is affecting your daily life, its exact position within the fundus, its size, and your reproductive plans. A fibroid that’s mostly outside the uterine wall in someone without symptoms needs a very different approach than one distorting the cavity in someone trying to conceive.