How is thrombocytopenia (low platelet count) managed in pregnancy?

Management of Thrombocytopenia in Pregnancy

Thrombocytopenia in pregnancy should be managed based on the underlying cause, severity of thrombocytopenia, and gestational age, with corticosteroids and IVIg as first-line treatments for ITP requiring intervention. 1, 2

Diagnosis and Differential Diagnosis

Thrombocytopenia in pregnancy (platelet count <150×10^9/L) occurs in 7-12% of pregnancies and requires careful evaluation to determine the underlying cause:

• Gestational thrombocytopenia (75% of cases):

  • Mild (typically >70×10^9/L)
  • Occurs in late gestation
  • No prior history of thrombocytopenia outside pregnancy
  • No fetal thrombocytopenia
  • Resolves spontaneously after delivery 1

• Other causes to consider:

  • Preeclampsia/HELLP syndrome
  • Immune thrombocytopenia (ITP)
  • Antiphospholipid syndrome
  • Thrombotic thrombocytopenic purpura
  • Hemolytic uremic syndrome
  • Acute fatty liver of pregnancy
  • DIC
  • Folate deficiency 1, 2

Monitoring and Treatment Thresholds

• First two trimesters: Treatment is generally not required unless:

  • Patient is symptomatic
  • Platelet count <20-30×10^9/L
  • Procedures are planned 1, 2

• Monitoring frequency:

  • Every 2-4 weeks initially
  • Increase frequency as delivery approaches
  • More frequent monitoring in third trimester as platelet counts may fall 2

Treatment Options

1. First-line treatments for ITP requiring intervention:

   • Corticosteroids: Prednisone 10-20 mg/day, adjusted to minimum effective dose

     • Monitor for worsening of hypertension, hyperglycemia, and osteoporosis
     • Requires more intensive glucose monitoring in diabetic patients 1, 2

   • IVIg: Consider when corticosteroids are ineffective or contraindicated 1, 2

2. Target platelet counts:

   • ≥50×10^9/L for cesarean section
   • ≥75×10^9/L for epidural/spinal anesthesia 1, 2

3. Medications to avoid due to potential teratogenicity:

   • Vinca alkaloids
   • Rituximab
   • Danazol
   • TPO-receptor agonists (romiplostim, eltrombopag)
   • Most immunosuppressive drugs (except azathioprine) 1, 2

Delivery Considerations

• Mode of delivery should be determined by obstetric indications rather than platelet count alone 2
• Collaboration among obstetrician, hematologist, anesthesiologist, and neonatologist is essential 1
• For pregnant women with ITP, the risk of neonatal thrombocytopenia is present but maternal platelet count does not reliably predict fetal platelet count 2

Special Considerations

• Refractory cases: In patients who have responded incompletely to prednisone and splenectomy, treatment preferences depend on platelet count and bleeding symptoms 1

  • For platelet counts <10×10^9/L with bleeding: IVIg, low-dose glucocorticoids, or high-dose glucocorticoids are preferred
  • For platelet counts 15-25×10^9/L with bleeding: IVIg, accessory splenectomy, or high-dose glucocorticoids are preferred

• Supportive care:

  • Consider antifibrinolytics for emergency treatment
  • For women with menorrhagia, progesterone-containing intrauterine devices or oral contraceptives can help control bleeding 1

Pitfalls to Avoid

• Misdiagnosis: Don't confuse gestational thrombocytopenia with ITP; thorough history is crucial
• Overtreatment: Asymptomatic mild thrombocytopenia (>70×10^9/L) usually requires monitoring only
• Inappropriate medication use: Avoid potentially teratogenic medications
• Inadequate monitoring: Increase frequency of platelet count monitoring as delivery approaches
• Failure to collaborate: Management requires coordination between multiple specialists

Pregnancy in women with ITP can generally proceed safely with low hemorrhagic risk for both mothers and infants when properly managed 1, 2.