Ectopic pregnancy

Background

• Must consider in all women of childbearing age who p/w abd/pelvic pain
• Leading cause of maternal death in first trimester
• Pregnancy in patient with prior tubal ligation or IUD in place is ectopic until proven otherwise (25-50% are ectopic)
• Even if an IUP is visualized, there is a small risk of heterotopic ectopic pregnancy
  • General Population = 1 per 4000
  • IVF Population = 1 per 100

Risk Factors

Risk Factors associated with Ectopic Pregnancy

Risk Factor	Odds Ratio
Previous tubal surgery	21
Previous ectopic pregnancy	8.3
Diethylstilbestrol exposure	5.6
Previous PID	2.4 to 3.7
Assisted Fertility	2 to 2.5
Smoker	2.3
Previous intrauterine device use	1.6

Work-Up

1. Hb (or CBC)
2. Beta-HCG (quantitative)
3. Type and Screen with Rh Factor
4. FAST and Pelvic US

Diagnosis

Clinical Features

1. Ruptured
   1. Shock
   2. Rebound tenderness
2. Non-ruptured (early)
   1. Abdominal/pelvic pain
   2. Vaginal bleeding

Diagnostic Algorithm

Estimating the Risk for Ectopic Pregnancy

Clinical Signs and Symptoms	Risk Group	Percent Risk of Ectopic (%)
Peritoneal irritation or cervical motion tenderness	High	29
No fetal heart tones; no tissue at cervical os; pain present	Intermediate	7
Fetal heart tones or tissue at cervical os; no pain		<1

• Using this algorithm should always favor considering ectopic if there is any evolution or change in a patient's clinical exam

Step one

• Assess for Shock
• If patient is a high risk for ectopic based on above estimation then immediately contact OBGYN

Step Two

Perform a Pelvic US

• Consider Transabdominal Ultrasound for B-HCG: >6000 mIU/ml (but if negative or indeterminate must do Pelvic US regardless of B-HCG)

Is there an Intrauterine Pregnancy?

• If there is an IUP and there was no assisted reproductive fertility used then ectopic ruled out and heterotopic unlikely (less than 1:30,000)
• If fertility assistance was used then still consider a heterotopic (1% risk)

Step Three

• If HCG above Discriminatory Zone (>1,500-3,000 mIU/ml) and not visualized it should be an ectopic pregnancy until proven otherwise

Step Four

• Arrange close followup for patients with no visualized IUP and B-HCG( (<1,500-3,000 mIU/ml), with minimal to no pain and hemodynamically stable.
• Patients should have a 48hr repeat B-HCG level checked to determine if appropriate doubling is occurring.

Repeat B-hCG Levels

Pregnancy Type	B-hCG Change
Normal	Increase >53% in 48hrs (until 10,000 mIU/ml) Depends on the initial value: <1500 --> 50% increase 1500-3000 --> 40% increase > 3000 --> 30% increase
Ectopic	Increases or decreases slowly ("plateau")^
Miscarriage	Decreases >20% in 48 hrs

^Initial level CANNOT be used to rule-out ectopic

Differential Diagnosis

Vaginal Bleeding in Pregnancy (<20wks)

• Ectopic pregnancy
• Subchorionic hematoma
• First Trimester Abortion
  • Complete Abortion
  • Incomplete Abortion
  • Inevitable Abortion
  • Missed Abortion
  • Septic abortion
  • Threatened Abortion
• Gestational trophoblastic disease
  • Consider when pregnancy-induced hypertension is seen before 24 wks of gestation
• Heterotopic pregnancy
• Implantation bleeding
• Molar pregnancy
• Non-pregnancy related bleeding
  • Cervicitis
  • Fibroids
  • Implantation bleeding

Acute Pelvic Pain

Differential diagnosis of acute pelvic pain

Gynecologic/Obstetric

• Normal variants
  • Nabothian cysts: Epithelial cells within mucous glans that appear as yellow inclusions on the cervix
  • Cervial Ectropion: Edothelial cells on the exterior of the cervix
  • Parous cervix: The is no longer round but may have multiple shapes after birth
• Pregnancy-related
  • Ectopic Pregnancy
  • Spontaneous abortion, threatened or incomplete
  • Septic abortion
• Acute Infections
  • Cervicitis
  • Endometritis
  • Bartholin gland abscess
  • Pelvic inflammatory disease (PID)
  • Tubo-ovarian abscess
• Vulvovaginitis
  • Bacterial Vaginosis
  • Candida Vaginitis
  • Trichomonas
  • Contact Vulvovaginitis
  • Atrophic vaginitis
• Adnexal Disorders
  • Hemorrhage/rupture of ovarian cyst
  • Ovarian torsion
  • Twisted paraovarian cyst
• Other
  • Myoma (degenerating)
  • Genitourinary trauma
  • Ovarian hyperstimulation syndrome
  • Sexual assault
• Recurrent
  • Mittelschmerz
  • Primary/Secondary Dysmenorrhea
  • Pelvic Congestion Syndrome
  • Endometriosis

Genitourinary

• Cystitis
• Pyelonephritis
• Urethritis (e.g. N. gonorrhoeae/Chlamydia)
• Urolithiasis

Gastrointestinal

• Gastroenteritis
• Appendicitis
• Bowel obstruction
• Perirectal abscess
• Diverticulitis
• Inflammatory bowel disease
• Irritable bowel syndrome
• Mesenteric adenitis

Musculoskeletal

• Abdominal wall hematoma
• Psoas hematoma, psoas abscess
• Hernia

Vascular

• Pelvic thrombophlebitis
• Abdominal aortic aneurysm
• Ischemic bowel (Mesenteric Ischemia)

Treatment

1. RhoGAM for all Rh- pts
2. OB/GYN Consult
3. Medical management with methotrexate (ACOG)
   1. Absolute contraindications
      1. Breast-feeding
      2. Laboratory evidence of immunodeficiency
      3. Preexisting blood dyscrasias (bone marrow hypoplasia, leukopenia, thrombocytopenia, or clinically significant anemia)
      4. Known sensitivity to methotrexate
      5. Active pulmonary disease
      6. Peptic ulcer disease
      7. Hepatic, renal, or hematologic dysfunction
      8. Alcoholism
      9. Alcoholic or other chronic liver disease
   2. Relative contraindications
      1. Adnexal mass >3.5 cm in largest diameter
      2. Presence of fetal heart rate
      3. Free fluid visualized in Pouch of Douglas
   3. Regimen choice
      1. hCG value <5000 mIU/ml --> single dose
      2. hCG value >5000 mIU/ml --> multi dose
   4. Note: Need to counsel patient to return after 4 and 7 days to recheck hCG values to check for satisfactory decline
4. OR, Surgery
   1. Salpingectomy vs. salpingostomy

External Links

• MDCalc - Pregnancy Due Dates Calculation

Source

• Barnhart KT. Ectopic Pregnancy [clinical practice]. N Engl J Med. 2009;361(4):379-387.