Currently our WebMD discussion on the side effects of endometrial ablation (EA) has nine pages of posts. It took me almost an hour of heavy-hearted reading to read every entry. Some 16 women stated that they had no further problems after their procedure. More than twice as many women reported continuing, or worsening, problems with pain in the pelvis, lower back, hip, or thigh. Some had the pain much of the time; others only monthly. Admittedly, our discussion forum is not a scientific study, but it made me wonder if one could predict who was more likely to have a good outcome—or who might be wise to consider another treatment option. Here are some of the possible reasons for a “bad outcome” after an EA.
Differences in types of EA procedures. While almost all EAs are done for a similar reason (abnormal/heavy uterine bleeding) there are a variety of methods used to destroy the lining of the uterus. These methods can be divided into two general groups:
1. First generation methods use a fiber optic light scope (hysteroscope) to actually look inside the uterus before and during the procedure. These have the advantage of “seeing” large polyps or other structural features which may be part of the bleeding problem. The disadvantages include need for surgical suite time and the risk of fluid overload when fluid is used to distend the uterus so all the walls can be seen. First generation procedures include:
Loop with an electric current
Rollerball with electric current
2. Second generation methods can be “blind,” without direct visualization of the lining. This means that this type of EA can be done in the GYN’s office. The GYN may not need to utilize fiber optic scope skills. Second generation procedures include:
ThermaChoice—hot water (190° F) in a balloon inside the uterus
HydroThermAblator—circulating hot water (190°) directly inside the uterus
Her Option—freezing or cryo destruction of the lining
NovaSure—mesh net triangle which conducts a bipolar radiofrequency
There are MANY studies which have compared at least two of these methods to see if one method is superior or works better with a certain type of patient. For example, 126 women were randomly assigned to NovaSure or ThermaChoice procedures. Five years after procedure, no further menstruation (“amenorrhea”) was reported by 48% in the mesh net group and 32% in the balloon group. Unfortunately, most of the comparison studies have had small numbers of women.
According to the largest review, there were no overall differences in patient satisfaction or bleeding outcome between all the first- and second-generation EA procedures. The advantage of the newer techniques (second-generation methods) were decreased risks for perforation through the wall of the uterus, less fluid overload, fewer tears of the cervix, and cervical scars which close off the cervical canal. However, women were more likely to have nausea, vomiting, and cramping.
Individual patient characteristics. So if the type of EA procedure seems to be generally equal, can we identify specific women who might not have as good an outcome based upon her medical history or personal anatomy? You may have read that large fibroids sticking out into the uterine cavity can impede the correct placement of NovaSure, or that a very large uterine cavity (e.g., greater than 5 inches) can be harder to treat.
Physicians from the Mayo Clinic reviewed the outcomes of 816 women who had an EA. Factors that seemed to predict successful stopping of all bleeding (“amenorrhea”) included: age 45 or older (menopause would be kicking in within five years or so), a thin uterine lining of less than 4 mm, normal size of uterine cavity (less than 9 cm), and use of NovaSure rather than a heated balloon. Patient characteristics linked to treatment failure were: age younger than 45 years, five or more pregnancies (leads to larger uterine size), prior tubal ligation, and a history of bad menstrual cramps. Of note, 5% of the women complained of pelvic pain after their EA procedure. Among that 5%, 40% had retained fluid within the uterus—referred to by the authors as “postablation syndrome.”
EA and adenomyosis. As many of you know, one can have endometriosis which invades into the muscular walls of the uterus. This is called adenomyosis. It is very difficult to diagnose; most often it is identified after removal of the uterus. Adenomyosis is not well visualized on ultrasound; an MRI may be needed. Like endometriosis it can worsen menstrual cramps, create uterine pain, and even prompt bleeding problems. I began to wonder if there was a link between continued pain after EA and possible undetected adenomyosis.
I found a study of 190 women with known adenomyosis who had a rollerball EA. After an average of five years follow up, almost 87% reported reduced or no menstrual cramps. This leaves 13% who had continued monthly pain. In a smaller study of women receiving microwave ablation, 59 had known adenomyosis. After an average of five years of follow up, younger age and presence of adenomyosis were found to be linked to unsatisfactory treatment outcomes.
The pain of endometriosis and adenomyosis can be referred from the uterus to the lower back, (e.g., like “back labor” during childbirth). Pain from the uterus may also be referred down the thigh. There can be many other causes of low back pain, including disc problems, muscle strain, and nerve entrapment. Thus it may be difficult to establish if back or pelvic pain after an EA was related to the EA or a concurrent medical condition.
In summary, abnormal uterine bleeding can be treated with medications and/or a synthetic progesterone containing IUD (“Mirena”). Surgical techniques such as hysteroscopy or endometrial ablation can be utilized to retain the uterus as a support for other pelvic structures. Even with these options a percentage of women will go on to have a hysterectomy because of continued symptoms.
If you are a woman contemplating an endometrial ablation, you might want to give some thought to possible factors which might decrease your satisfaction with an EA. It is certainly worth discussing with your GYN. I think Leah, posting in 2009, said it best: “To all the women reading this—yes, good things will come with your choice (EA or other) but not perfection. Choose wisely, then live happy.”