e6-13: Chronic Pelvic Pain in Women

Chronic pelvic pain is defined as noncyclic pain lasting at least 3–6 months that localizes to the pelvic girdle region; it must be of sufficient severity to cause functional disability or necessitate medical care. This disorder is common, accounting for 10–20% of outpatient visits to a gynecologist, and is associated with decreased quality of life, depression, and sexual dysfunction. Patients with chronic pelvic pain may also experience marital stress, altered relationships at home, and decreased work capacity.

Chronic pelvic pain is a symptom that can arise from a diverse group of disorders, including gynecologic, urologic, gastrointestinal, musculoskeletal, or neurologic abnormalities. Gynecologic conditions that can cause chronic pelvic pain include endometriosis, pelvic adhesions, chronic pelvic inflammatory disease, ovarian remnant, pelvic congestion syndrome, and adenomyosis. Interstitial cystitis, irritable bowel syndrome, and pelvic floor myalgia have all been associated with chronic pelvic pain. Musculoskeletal and neurologic causes of pelvic discomfort should also be considered, including disk herniation, lumbar spondylosis, and nerve entrapment. It is important to remember that some women may have more than one diagnosis contributing to their pain. Chronic pelvic pain may also be diagnosed in the absence of clear identifiable underlying pathology.

A. Symptoms and Signs

Certain features of the history and physical examination can provide clues to the underlying diagnosis. Patients should be asked about the location, quality, and intensity of their pain as well as the relationship with the menstrual cycle, sexual activity, urination, and defecation. Dysmenorrhea and dyspareunia are often experienced by patients with endometriosis, whereas dysuria, urgency, and frequency in association with pelvic pain are characteristic of interstitial cystitis. Patients with irritable bowel syndrome often report abdominal pain, distention, and diarrhea or constipation. Clinicians should ask patients about surgery or direct trauma involving the spine or pelvis, which may suggest musculoskeletal sources of pain. In addition, a thorough gynecologic and obstetric history should be obtained in all women.

Guidelines emphasize the importance of evaluating the impact of the patient's chronic pelvic pain on her quality of life, psychological health, and relationships. The International Pelvic Pain Society has developed a detailed questionnaire that patients can complete prior to the office visit. This survey asks patients to rate the effect of their pain on their emotional well-being and daily functioning and can provide the clinician with valuable information. Additional items on the survey assess for occurrences of physical, sexual, or emotional abuse, which may be risk factors for chronic pelvic pain.

The physical examination, including the pelvic examination, is usually quite painful in the patient with chronic pelvic pain and should be done carefully. Guidelines recommend performing the physical examination in a particular order, progressing sequentially from the musculoskeletal examination to the examination of the cervix to minimize pain and discomfort. The examination should begin with palpation of the thoracic and lumbar spine, pelvic girdle, and abdomen, which may reveal areas of tenderness that refer to the pelvic area. A positive Carnett test (an increase in pain when the abdominal muscles are tensed) can be helpful for identifying abdominal wall trigger points.

Next, examination of the external genitalia should be performed using a cotton swab to carefully identify areas of vulvar sensitivity. The single-digit internal vaginal examination is helpful for localizing exact areas of pain, palpating specific pelvic structures (cervix, urethra, bladder base), and assessing for trigger points along the pelvic floor muscles. Palpation of the pelvic viscera can help identify localized areas of tenderness in women with endometriosis or chronic pelvic inflammatory disease. The cervical examination may be performed with a small speculum and should assess for cervical lesions, mucosal abnormalities, and evidence of infection; tenderness localized to the cervix or vaginal fornices may be elicited by palpation with a long cotton swab.

When examining a patient where there is high likelihood of myofascial pain, a standardized examination can be performed that includes palpation of the sacroiliac joints while the patient is seated followed by palpation of the medial anterior superior iliac spine and specific pelvic floor muscles while the patient is supine; the degree of pain experienced by the patient with each maneuver is noted and a diagnosis of myofascial pain is likely when patients have pain at four or greater sites.

B. Laboratory Findings

Laboratory evaluation should be guided by the history and physical examination findings. Testing may include a urinalysis, screening for chlamydia and gonorrhea, or cervical cytology.

C. Diagnostic Testing and Imaging

Transvaginal ultrasonography is useful to confirm a suspected diagnosis, such as an ovarian endometrioma or adenomyosis. Laparoscopy is considered the gold standard for diagnosis of gynecologic disorders, such as endometriosis or pelvic adhesions.

Chronic pelvic pain may be associated with gynecologic and nongynecologic conditions; it is not uncommon for more than one causative diagnosis to be present in a woman. Gastrointestinal disorders (irritable bowel syndrome) and functional urinary syndromes (interstitial cystitis) are common nongynecologic diagnoses that may contribute to chronic pelvic pain. Clinicians should perform a careful examination of the gastrointestinal, urologic, musculoskeletal, and neurologic systems in order to evaluate for these possibilities.

Successful treatment of chronic pelvic pain often requires a multidisciplinary approach, recognizing its impact on a patient's quality of life, psychological health, relationships, and work. Health psychologists, psychiatrists, pain specialists, and physical therapists may all play important roles in helping the patient to manage her symptoms and maximize her daily functioning and well-being.

A. Medical Treatment

Medical therapy may be general (focused on overall management of the pain) or disease-specific (focused on specific underlying etiologies of pain). The choice of medical therapy should be influenced by side-effect profiles as well as the patient's interest in pregnancy.

General therapies include medications that are often used for the treatment of chronic pain syndromes. Initial treatment may begin with simple analgesics, such as acetaminophen or nonsteroidal anti-inflammatory drugs (NSAIDs). Some women may also benefit from neuromodulators, including tricyclic antidepressants, duloxetine, gabapentin, and pregabalin. Guidelines acknowledge the limited evidence for the effectiveness of these treatments for the management of chronic pelvic pain; the potential for side effects (such as gastrointestinal and renal side effects with NSAIDs) may limit long-term use of some treatments.

Hormonal therapies are used primarily for treating gynecologic sources of chronic pelvic pain. Women with suspected endometriosis can be empirically treated with hormonal therapy before diagnostic laparoscopy is performed. Combined oral contraceptives, progestins (oral, injectable, and intrauterine), gonadotropin-releasing hormone (GnRH) analogs, and danazol are effective for treating the dysmenorrhea associated with endometriosis, although the side effects vary. The effects on bone mineral density associated with GnRH analog therapy can be mitigated by "add-back" low-dose hormonal therapy (norethindrone, low-dose estrogen, or a combination of estrogen and progesterone), which may also provide symptomatic relief for associated hot flashes and vaginal symptoms. Danazol may be associated with severe androgenic side effects, including hirsutism, acne, and weight changes; therefore, it is not used as first-line therapy. For women who have endometriosis and desire pregnancy, NSAIDs may provide symptomatic relief.

A Cochrane systematic review and meta-analysis investigated the effectiveness of noninvasive treatments for the management of chronic pelvic pain unrelated to endometriosis, primary dysmenorrhea, chronic pelvic inflammatory disease, or irritable bowel syndrome. Treatment with medroxyprogesterone, compared to placebo, was associated with a reduction in pain that was maintained up to 9 months after therapy; side effects included weight gain and bloating.

Musculoskeletal sources of chronic pelvic pain include pelvic floor myalgia, which is related to spasm of the levator ani muscles, and myofascial trigger points. Treatments include referral to pelvic physical therapy and, if needed, trigger point injections with a local anesthetic or botulinum A toxin.

Treatment of irritable bowel syndrome and interstitial cystitis are discussed in Chapters 15-05, 15-06 and 23-04.

B. Surgical Treatment

Women with endometriosis may be offered laparoscopic surgical destruction of implants; adhesiolysis can be considered if severe and dense adhesions are also present. Uterine artery ablation has been shown to be effective for the treatment of adenomyosis, and pelvic vein embolization improves pain in patients with pelvic venous congestion.

Guidelines note that additional surgical techniques for the management of chronic pelvic pain include presacral neurectomy, laparoscopic uterine nerve ablation, hysterectomy, and salpingo-oopherectomy.

• Patients with chronic pelvic pain benefit from a multidisciplinary approach to their care. Clinicians should consider referring to health psychologists, pain specialists, and sex therapists early in the course of treatment.

• Patients should be referred to a gynecologist for diagnostic or therapeutic surgical procedures, if the underlying diagnosis is unclear, or if expertise is needed to manage the side effects associated with medical treatments (ie, GnRH agonist therapy).