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Cardiology62 papers

Fetal anemia

Last edited: 4/15/2026

Overview

Fetal anemia refers to a reduction in red blood cell mass in the fetus, often leading to hemodynamic instability and growth restriction. It can be caused by various factors, including vascular anomalies such as extra-abdominal umbilical vein varix, which can provoke hemolytic processes 1.

Diagnosis

  • Key Diagnostic Criteria: Elevated middle cerebral artery peak systolic velocity (≥1.5 MoM) suggesting fetal anemia 1.
  • Recommended Tests: Doppler ultrasound assessment, particularly focusing on middle cerebral artery Doppler for anemia screening 1.
  • Additional Findings: Fetal cardiomegaly, decreased fetal movements, and umbilical vein varix detected via ultrasound 1.
  • Management

  • First-Line Treatments: Intrauterine transfusions to address severe anemia and circulatory failure 1.
  • Adjunctive Measures: Close monitoring of fetal status post-transfusion to prevent complications and manage nonreassuring fetal conditions 1.
  • Special Populations

  • Pregnancy: Extra-abdominal umbilical vein varix associated with significant perinatal risks including fetal heartbeat abnormalities and increased risk of fetal death 1.
  • Key Recommendations

  • Antenatal surveillance with Doppler ultrasound is crucial for early detection of fetal anemia in cases with umbilical vein varix 1 (Evidence: Moderate).
  • Intrauterine transfusion should be considered for severe fetal anemia to improve fetal outcomes and prolong gestation 1 (Evidence: Weak).
  • Prompt delivery by cesarean section may be necessary if fetal status remains nonreassuring despite interventions 1 (Evidence: Expert opinion).
  • References

    1 Io S, Kondoh E, Iemura Y, Minamiguchi S, Chigusa Y, Mogami H et al.. Severe fetal anemia as a consequence of extra-abdominal umbilical vein varix: A case report and review of the literature. Congenital anomalies 2021. link

    Original source

    1. [1]
      Severe fetal anemia as a consequence of extra-abdominal umbilical vein varix: A case report and review of the literature.Io S, Kondoh E, Iemura Y, Minamiguchi S, Chigusa Y, Mogami H et al. Congenital anomalies (2021)

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