What are the pros and cons of uterine artery embolization?

During uterine artery embolization, the blood vessels that supply the fibroid are closed off under local anesthetic. The doctor makes a small cut in the groin and inserts a thin plastic tube ( catheter) into the femoral artery. A contrast medium (dye-like substance) is injected so that the blood vessels can be seen on the X-ray. The catheter is then pushed through to the fibroid using the X-ray to guide the way. Tiny plastic particles are then injected into the blood vessels in the fibroid via the catheter. The particles block the blood vessels, stopping the flow of blood to the fibroid.

The procedure lasts between one and two hours. Eight to twelve hours' bed rest are then needed for the cut in the groin to be able to close up again.

A few weeks after this procedure, magnetic resonance imaging (MRI) is used to check whether the treatment had the desired effect – in other words, whether the blood supply to the fibroid has been completely cut off. Only then do the fibroids gradually shrink and the symptoms go away. The particles stay in the remaining fibroid tissue.

Like surgery, embolization is generally an option for women who have been experiencing severe symptoms because of their fibroids for a long time. Symptoms improve in around 80 to 90 out of 100 women following the treatment. Around 10 out of 100 women don't notice an improvement after the procedure.

New fibroids may grow afterwards. In some women, uterine artery embolization doesn't work well enough, or the positive effect is only temporary. For this reason, about 20 out of 100 women needed further treatment in the first few years after the procedure. They either had the same procedure done again or another type of surgery.

Some fibroids can't be treated using embolization. They include submucosal fibroids (just under the lining of the womb) and pedunculated subserosal fibroids (on the outside of the womb). Surgery is the preferred treatment for those kinds of fibroids.

There are other reasons not to use embolization, for example if the woman is pregnant or has a genital infection. Embolization is also not an option for women with a very overactive thyroid because they wouldn't tolerate the iodine in the contrast medium.

People often have cramping abdominal pain after embolization. Nausea, vomiting and fever are also possible. These side effects may last for a few days, but can be treated with medication. In 3 out of 100 women, embolization leads to problems that have to be treated, such as an infection in the womb, damage to blood vessels or deep vein thrombosis in the legs.

Embolization may also make a woman's period stop completely. This happens in about 4 out of 100 women. In about 5 out of 100 women the treated fibroids become detached and leave the body through the vagina.

Research suggests that uterine artery embolization can affect fertility. One explanation for that is that the tiny plastic particles sometimes mistakenly get into blood vessels in the ovaries, reducing the blood circulation there. Although some women become pregnant after embolization, it does become somewhat less likely. There is also an increased risk of miscarriage. Whether uterine artery embolization is an option for a woman who still wants to have a baby depends on what other alternatives she has and how bad the symptoms are.

A small number of studies have compared the outcomes of uterine artery embolization with those of hysterectomy (surgical removal of the womb) and myomectomy (surgical removal of the fibroid/s). The participants in these studies were women who hadn't been through the menopause and had heavy periods because of their fibroids.

Three studies with a total of about 290 women compared uterine artery embolization with hysterectomy according to the following criteria:

• Satisfaction with the treatment after two years: The participants in both groups were similarly satisfied with the outcome of the treatment.
• Length of time spent in hospital: Women who had uterine artery embolization recovered quicker and were able to leave the hospital around three days earlier than those who had had a hysterectomy.
• Severe complications: These occurred in about 1 out of 100 women in each group.
• Need for further treatment: 22 out of 100 women had treatment again within two years of an initial embolization procedure, and 9 out of 100 women had treatment again after hysterectomy.

Summary: One main advantage of embolization is that the womb is not removed. The treatment and recovery time is also shorter than with hysterectomy. But further treatments are more likely to be needed after embolization. Side effects are also more common shortly after this treatment. There is a lack of research comparing the long-term effects of the treatments.

Two studies with a total of about 240 women compared uterine artery embolization with myomectomy according to the following criteria:

• Satisfaction with the treatment after two years: The participants in both groups were similarly satisfied with the outcome of the treatment.
• Length of time spent in hospital: Women who had uterine artery embolization recovered faster and were able to leave the hospital around one day earlier than those who had a myomectomy.
• Fertility: 23 out of 100 women had children after the embolization procedure, compared to 48 out of 100 after myomectomy.
• Severe complications: These occurred in about 1 out of 100 women in each group.
• Need for further treatment: about 23 out of 100 women had treatment again within two years of an initial embolization procedure, and around 4 out of 100 women had treatment again after myomectomy.

Summary: There isn't enough research comparing the advantages and disadvantages of uterine artery embolization with those of myomectomy. These results should therefore be interpreted with caution. One likely benefit of uterine artery embolization is the faster recovery after the procedure. A general anesthetic is also not needed. The chances of having a child after embolization are possibly lower than after myomectomy. Women are also more likely to need further treatments after embolization. Both procedures probably relieve the symptoms equally well in the short term. There is no research on whether this is also the case in the long term.