May 22,2023

TOG Article April 2023: Non-immune Hydrops fetalis

Key content

  • Hydrops fetalis is the accumulation of two or more fetal fluid collections, including pericardial effusion, pleural effusion(s), ascites and skin oedema.
  • In the absence of red cell alloimmunisation, hydrops fetalis is non-immune and affects approximately 1 in 2000 pregnancies.
  • Non-immune hydrops fetalis (NIHF) is associated with severe perinatal morbidity/mortality and significant maternal risks, including maternal mirror syndrome.
  • Priorities for clinicians are determining the cause antenatally to optimise management and discuss treatment options, if available.
  • Systematic reviews have indicated that a cause can be identified prenatally in ~60% cases. Recent evidence indicates fetal exome sequencing can provide a diagnosis in 30% of previously unexplained cases.