Pelvic Pain
Sara Pentlicky
Courtney Schreiber
INTRODUCTION
Knowledge regarding the location of organs in the female pelvic region and how they may cause discomfort is key to the evaluation of pelvic pain in female patients. There may be distinct causes of pelvic pain depending on the timing and onset of pain. Acute pelvic pain is intense with a sudden and sharp onset of short duration. Chronic pelvic pain has been present for >6 months and is severe enough to cause functional disability.
DIFFERENTIAL DIAGNOSIS LISTAcute Pelvic Pain
Obstetric—ectopic pregnancy, abortion (threatened, missed, or incomplete), and labor
Gynecologic—endometriosis, adenomyosis, dysmenorrhea, mittelschmerz, pelvic adhesions, ovarian/adnexal torsion, stable/ruptured ovarian cyst, and obstructive Müllerian tract anomaly
Infectious—endometritis, pelvic inflammatory disease (PID), and tubo-ovarian abscess
Gastrointestinal—gastroenteritis, appendicitis, Meckel diverticulitis, pancreatitis, inflammatory bowel disease, constipation, volvulus, intestinal obstruction, irritable bowel syndrome, mesenteric adenitis, and regional enteritis
Genitourinary—cystitis, radiation cystitis, urinary tract infection, pyelonephritis, and ureteral/renal lithiasis
Musculoskeletal—hernia, back pain, pelvic bone and joint infection, slipped femoral epiphysis, and muscular strain/sprain
Others—falls, accidents, and sexual abuse
Chronic Pelvic Pain
Obstetric—pregnancy
Gynecologic—obstructive Müllerian tract anomaly, cervical stenosis, ovarian tumor, pelvic adhesions, and endometriosis
Gastrointestinal—hernia, inflammatory bowel disease, irritable bowel syndrome, midgut malrotation, lactose malabsorption, and chronic constipation
Genitourinary—ureteropelvic junction obstruction, detrusor instability, pelvic kidney, and cystitis
Musculoskeletal—scoliosis, kyphosis, fibromyalgia, and abdominal wall trigger points
Neurologic—neurofibromatosis and nerve entrapment syndrome
Psychological—abuse and emotional stress
DIFFERENTIAL DIAGNOSIS DISCUSSION
Ectopic Pregnancy
Etiology
An ectopic pregnancy is one in which a fertilized ovum implants itself outside the uterine cavity (most often in the fallopian tube) as a result of delayed passage of the fertilized ovum into the uterine cavity. Abdominal, cornual, cervical, and ovarian ectopic pregnancies can also occur. Delayed passage of the fertilized ovum into the uterine cavity usually results from a condition that interferes with tubal structure or function (e.g., chronic salpingitis, pelvic adhesive disease, tubal surgery, congenital abnormalities of the fallopian tube).
Clinical Features
The classic triad of symptoms consists of abdominal pain, history of amenorrhea, and new vaginal bleeding, which is present in about 50% of patients. The abdominal pain may develop suddenly or gradually. In unruptured ectopic pregnancies, the pain tends to be unilateral, colicky, and localized to the involved adnexa. In case of a rupture, the pain becomes diffuse and intense. Referred shoulder pain may occur in the presence of hemoperitoneum. Dizziness and syncope are the result of anemia and hypotension.
Evaluation
Vital signs. Vital signs are often within the normal limits. However, with excessive pain and/or blood loss, the patient may be tachycardic. If there has already been significant blood loss, patient may also be hypotensive.
Abdominal examination. Localized tenderness may be revealed in the lower quadrant. With rupture and intra-abdominal bleeding, rebound tenderness and guarding may be elicited. On pelvic examination, the cervix and uterus may be soft and tender from the effects of pregnancy hormones. Adnexal fullness or a discrete, tender mass may be noted in some patients.
Complete blood count (CBC). The hemoglobin and hematocrit values may be low in patients with acute or gradual intraperitoneal hemorrhage; in the absence of bleeding, they are usually normal.
Type and screen. Rh status is assessed in case blood replacement is necessary, and Rh-negative patients who may need Rhogam are identified.
A pregnancy test. A quantitative beta human chorionic gonadotropin (betahCG) should be drawn.
Vaginal ultrasonography can detect an intrauterine gestational sac as early as 4 weeks of gestation when the quantitative β-hCG is 1,500 to 2,000 mIU/mL. However, distinguishing between an intrauterine gestational sac and endometrial fluid, sometimes referred to as a pseudosac, can be difficult. A pseudosac can form when an ectopic pregnancy causes changes within the uterus. Therefore, the clinician performing the ultrasound should identify other markers of an intra- or extrauterine pregnancy (i.e., double decidual sign). In addition, the ultrasound may show an adnexal mass or complex free fluid in the pelvis. An adnexal mass seen on ultrasound further substantiates the diagnosis of an ectopic pregnancy. Free fluid in the cul-de-sac seen
on ultrasound suggests hemoperitoneum and the necessity of early surgical intervention.
HINT: A quantitative β-hCG >2,000 mIU/mL and an empty uterus by vaginal ultrasound is presumptive evidence of an ectopic pregnancy.Treatment
Surgical diagnosis and treatment via laparoscopy or laparotomy is almost always indicated to manage an ectopic pregnancy with a tubal mass ≥3.5cm. Medical treatment with methotrexate can be considered when an intrauterine pregnancy is absent, no adnexal mass is present, or the mass is > 3.5 cm in the setting of a positive β-hCG. Early gynecology consultation is highly recommended.
Dysmenorrhea
Etiology
Primary dysmenorrhea is painful menstruation with no demonstrable cause. Patients with primary dysmenorrhea have a greater endometrial production of prostaglandins, which cause uterine contractions, uterine ischemia, and pelvic pain.
Secondary dysmenorrhea results from various pathologic conditions (e.g., endometriosis, salpingitis, or congenital Müllerian anomalies).
Clinical Features
Symptoms of primary dysmenorrhea usually begin 1 to 2 years after menarche when ovulatory cycles are established. The pain is described as crampy, lower abdominal pain, starting within several hours of the onset of menses. The pain usually lasts for 2 to 3 days. Associated symptoms include headache, nausea, vomiting, diarrhea, and backache. The symptoms of secondary dysmenorrhea are similar to those of primary dysmenorrhea, although they develop years after menarche.
Evaluation
In patients with primary dysmenorrhea, the physical examination is normal. Findings in secondary dysmenorrhea are related to the underlying cause. A CBC and screening tests for Neisseria gonorrhoeae and Chlamydia trachomatis are obtained to evaluate for possible infection. A pregnancy test is obtained to rule out pregnancy. Pelvic ultrasonography is useful for delineating the internal pelvic anatomy and evaluation of adnexal pathology. Magnetic resonance imaging (MRI) is helpful in the diagnosis of Müllerian abnormalities.
Treatment
If the pelvic examination is normal, treatment is aimed at symptomatic relief. Nonsteroidal anti-inflammatory drugs (NSAIDs) should be initiated 1 day prior to expected menses and continued for 2 to 3 days. If dysmenorrhea persists, a trial of combination oral contraceptives (COCs) may be initiated. COCs may
also be used continuously to decrease the number of withdrawal bleeds. While irregular spotting may occur with this method, number of bleeding days and symptoms of dysmenorrhea often decrease. Depot medroxyprogesterone acetate (DMPA), commonly known as Depo-Provera ®, may also improve symptoms in the setting of primary dysmenorrhea. Furthermore, Implanon ®, a single subdermal rod impregnated with etonogestrel, has been shown to improve dysmenorrhea due to specific causes of pelvic pain (i.e., endometriosis); thus, Implanon ® could be used in this setting. When the pain is refractory to all medical therapy, a diagnostic laparoscopy is warranted to evaluate for pelvic pathology, such as endometriosis, adhesions, or ovarian cysts.
also be used continuously to decrease the number of withdrawal bleeds. While irregular spotting may occur with this method, number of bleeding days and symptoms of dysmenorrhea often decrease. Depot medroxyprogesterone acetate (DMPA), commonly known as Depo-Provera ®, may also improve symptoms in the setting of primary dysmenorrhea. Furthermore, Implanon ®, a single subdermal rod impregnated with etonogestrel, has been shown to improve dysmenorrhea due to specific causes of pelvic pain (i.e., endometriosis); thus, Implanon ® could be used in this setting. When the pain is refractory to all medical therapy, a diagnostic laparoscopy is warranted to evaluate for pelvic pathology, such as endometriosis, adhesions, or ovarian cysts.
Adnexal Torsion
Etiology
Adnexal torsion is the twisting of a fallopian tube or both the fallopian tube and the ovary on its pedicle. This may result in vascular occlusion, ischemia, and tissue death. Usually, a normal tube or ovary does not “twist” without predisposing factors (e.g., ovarian cysts, tumors, tubal neoplasm, parovarian cysts, or pregnancy). The risk of ovarian torsion is greatest if there is an ovarian cyst >5 cm.
Clinical Features
Abdominal pain may develop suddenly or gradually. It is usually paroxysmal and intermittent. It tends to be unilateral and localized to the involved adnexa. If ischemia occurs, the pain worsens and becomes persistent. Associated symptoms include nausea, vomiting, anorexia, and a sense of fullness in the lower abdomen.
