Dysfunctional Uterine Bleeding (DUB)

What is Dysfunctional Uterine Bleeding?

DUB is excessive uterine bleeding that is not caused by an organic (anatomic) condition. DUB should not be diagnosed in the presence of the following conditions: endometrial polyps, uterine fibroids, adenomyosis, endometrial or cervical cancer, pelvic infection including endometritis (infection of the lining of the uterus), endometriosis, polycystic ovarian disease, ovarian cyst or tumor, thyroid dysfunction (hypo- or hyperthyroidism) or blood clotting abnormalities (coagulopathy). Hence, DUB can be diagnosed only after comprehensive testing that effectively rules out all the above conditions. Failure to perform sufficient testing may result in an incorrect diagnosis of DUB because the true cause of the abnormal bleeding has been overlooked. An erroneous diagnosis of DUB may lead to improper and failed treatment. The current literature indicates that a diagnosis of “DUB” accounts for approximately 20% of all hysterectomies in the U.S.

Which Tests are Required for Accurate Diagnosis of DUB?

For a correct diagnosis, a series of sequential tests may be required. Testing must continue to exclude multiple conditions as described in the previous paragraph. It is now clear from multiple research studies that the traditional approach of an endometrial biopsy or D&C alone is inadequate to exclude many benign and malignant conditions.

Endometrial biopsy and/or D&C may detect endometritis (infection of the endometrial lining), endometrial hyperplasia (if it is generalized), polyps, and cancer. However, certain conditions which may be localized may be missed in over 50% of endometrial biopsy/D&C procedures. These include localized hyperplasia, endometrial cancer, endometrial polyp, and fibroids. When endometrial biopsy/D&C results in a positive diagnosis, this diagnosis is generally reliable. However, when these procedures are “negative,” this does not exclude significant abnormality and additional testing may be required.

More effective diagnostic measures for evaluating women with abnormal bleeding are available. These include transvaginal pelvic ultrasound, sonohysterography (an ultrasound procedure), and hysteroscopy (combined, if necessary, with D&C). In special cases, other tests may be helpful, including laparoscopy, MRI (magnetic resonance imaging), cervical culture, pituitary and thyroid gland function tests, and blood tests for blood clotting defects.

The choice of the initial test and the sequence of testing will depend upon the history, the findings on physical examination, the imaging resources available, and the expertise of the physician. Transvaginal pelvic ultrasound can effectively detect abnormalities of the uterus and ovaries. It can be helpful to diagnose polycystic ovaries, ovarian cysts, other masses, endometrial thickening, and fibroids. The thickened endometrium may be caused by polyps, endometrial hyperplasia, endometrial cancer, and submucous fibroid, so additional testing may be required for further clarification.

The best next step is sonohysterography (SHG). Where SHG is not available, hysteroscopy may be required. Sonohysterography (or hysterosonography) is a procedure that involves placing a thin catheter into the cervix through which sterile fluid is injected into the uterine cavity while observing with ultrasound. With the cavity distended by fluid, the cause of bleeding or endometrial thickening can be seen. By means of SHG a polyp can be clearly distinguished from a fibroid; endometrial hyperplasia or cancer may appear as an irregular thickening that is localized or generalized. These findings not only help determine the cause of abnormal bleeding but also help determine the best therapeutic approach. For example, with fibroids, SHG helps to determine what kind of surgery is possible (i.e., abdominal or vaginal). For other conditions, SHG helps to decide between D&C or hysteroscopy (a localized lesion is more reliably approached with hysteroscopy, whereas a generalized abnormality can be approached by D&C).

In some cases, SHG can show that there is no abnormality in the uterus and, therefore, no surgical procedure is required. Adenomyosis is a common condition in women in their 30s and 40s and often coexists with fibroids. Because it is more difficult to diagnose (compared to fibroids) by routine diagnostic tests, adenomyosis is often not considered or is misdiagnosed as fibroids. However, in expert hands (and when appropriately suspected) this diagnosis can be made by means of high-resolution transvaginal ultrasound. Occasionally, adenomyosis is detected on an X-ray (hysterosalpingography).

Currently, the most effective diagnostic test is MRI (magnetic resonance imaging). Laparoscopy refers to the exploration of the pelvis and abdominal cavity by means of a telescope which is usually inserted through the navel; cultures and biopsies can be obtained as needed. It can assist in the diagnosis of chronic pelvic inflammatory disease, pelvic adhesions, endometriosis, and other conditions which usually require direct visualization for definitive diagnosis.

Conclusion: DUB is a diagnosis of exclusion. Only after ruling out a long list of conditions is it acceptable to diagnose DUB and treat as such. It is unacceptable to treat a woman with undiagnosed abnormal bleeding on the assumption that it is DUB. Such treatment will often fail and, unfortunately, may lead to an unnecessary hysterectomy.

What is the Medical Treatment for True DUB?

DUB may be severe enough to cause anemia. Several measures may help non-steroidal anti-inflammatory drugs (such as ibuprofen), progestins (provera and others), birth control pills, danazol (a weak androgenic hormone that causes suppression of ovarian estrogen/progesterone production), and GnRH agonists (gonadotropin-releasing hormone agonists) such as Lupron, which lead to suppression of ovarian estrogen/progesterone production.

What is the Surgical Treatment for DUB?

Surgery is indicated only after all the medical measures have failed. Endometrial ablation is a first-line option in surgical treatment. This is an outpatient hysteroscopic operation that is scheduled after “shrinking” the endometrium with an 8-week course of Danazol or GnRH agonists. The hysteroscope is inserted into the uterine cavity under general anesthesia. The endometrial lining is ablated using laser, electrical coagulation, or other techniques. A balloon inserted into the endometrial cavity through the cervix and filled with hot water is another technique to ablate the endometrium. Endometrial ablation may resolve DUB in 70-80% of cases. However, 25% of treated women have recurrent DUB, and repeat ablation may be required.

Hysterectomy as a treatment for DUB should be considered only as a last resort. In my experience, treatment failure requiring hysterectomy is rare indeed. The liberal use of hysterectomy to “treat DUB” reflects the failure to identify an organic cause for abnormal uterine bleeding which is present in most women. When the diagnosis of DUB is correct, for most women a safe effective non-surgical approach or limited surgical treatment is usually available.