Ovarian hyperstimulation syndrome

Background

  • Fertility treatments causing development of multiple follicles at once
    • Exaggerated ovarian response to ovulation induction (esp in IVF when HCG is used to stimulate)
  • Fluid shifts out of vasculature (third spacing)
  • Typically 5-10d after 1st dose
  • Ranges in severity from mild to severe multiorgan dysfunction, relating in part to massive intravascular fluid shifts

Clinical Features

Differential Diagnosis

Pelvic Pain

Pelvic origin

Abdominal origin

Evaluation

Pelvic ultrasound (sagittal) in woman with OHSS showing ascites and enlarged ovary (diameter = 6.5mm)

Workup

Evaluation[1].

Classification Clinical features Lab findings
Mild Normal
Moderate Above plus:
  • Ultrasonographic evidence of ascites
  • Elevated hematocrit (>41%)
  • Elevated WBC (>15,000/mL)
  • Hypoproteinemia
Severe Above plus:
  • Hemoconcentration (hematocrit >55%)
  • WBC >25,000/mL
  • Serum creatinine >1.6mg/dL
  • Creatinine clearance <50 mL/min
  • Hyponatremia (Na+ <135 mEq/L)
  • Hyperkalemia (K+ >5 mEq/L)
  • Elevated liver enzymes
Critical Above plus: Worsening findings

Management

Pregnant patients must be followed very closely, as they are likely to worsen

  • Urgent GYN consultation for all

Mild

  • Pain control
  • Encourage oral fluids (1-2 liters/day)
  • Ambulate, but avoid other physical activity. Avoid sexual intercourse

Moderate

  • IV fluids (e.g normal saline)
  • Therapeutic paracentesis if ascites (aspirate 0.5-4 L)
  • Thromboembolic prophylaxis (e.g. LMWH)
    • All hospitalized patients
    • Outpatients with 2-3 risk factors:
      • Age >35 years
      • Obesity
      • Immobility
      • Personal or family history of thrombosis
      • Thrombophilias
      • Pregnancy

Severe

Critical

  • As above + resuscitative care

Disposition

  • Mild: outpatient
    • Avoid heavy physical activity
    • Return for
      • Worsening abdominal pain
      • Weight gain (>1 kg/day)
      • Increasing abdominal girth
  • Moderate: outpatient if close follow-up (discuss with GYN)
  • Severe: admit
  • Critical: ICU

Complications

See Also

References

  1. Navot D, Bergh PA, Laufer N. Ovarian hyperstimulation syndrome in novel reproductive technologies: prevention and treatment. Fertil steril 1992; 58:249. From: Fiedler K, Ezcurra D. Predicting and preventing ovarian hyperstimulation syndrome (OHSS): the need for individualized not standardized treatment. Reprod Biol Endocrinol 2012; 10:32. Copyright © 2012 Fiedler and Ezcurra. Reproduced from BioMed Central Ltd