What is the workup for a pregnant patient with fetal hydrops (fetal edema)?

From the Guidelines

The workup for a pregnant patient with fetal hydrops should begin with a detailed ultrasound, including fetal echocardiogram, to assess the severity and distribution of fluid accumulation, followed by maternal history, including family history, medications, and exposures, as recommended by the Society for Maternal-Fetal Medicine 1. The initial evaluation should also include an antibody screen to verify that it is nonimmune, targeted sonography with echocardiography to evaluate for fetal and placental abnormalities, MCA Doppler evaluation for anemia, and fetal karyotype or chromosomal microarray analysis, regardless of whether structural fetal anomalies are identified 1. Key components of the workup include:

• Detailed ultrasound to assess fetal anatomy and fluid accumulation
• Fetal echocardiography to evaluate cardiac structure and function
• Middle cerebral artery Doppler studies to identify fetal anemia
• Maternal serum screening for conditions like alpha thalassemia and genetic carrier testing
• Amniocentesis to evaluate for chromosomal abnormalities, genetic disorders, and fetal infections
• Infectious disease testing, including TORCH panel The prognosis depends on the underlying etiology, response to therapy if treatable, and the gestational age at detection and delivery, with aneuploidy conferring a poor prognosis, and even in the absence of aneuploidy, neonatal survival is often <50% 1. The goal of the workup is to identify the underlying cause of fetal hydrops and tailor management accordingly, which may include intrauterine transfusions for anemia, medications for arrhythmias, or delivery planning for structural abnormalities, with consultation with maternal-fetal medicine specialists, pediatric cardiologists, and neonatologists essential for coordinated care 1.

From the Research

Workup for Fetal Hydrops

The workup for a pregnant patient with fetal hydrops (fetal edema) involves a comprehensive evaluation to determine the underlying cause of the condition.

• A detailed ultrasound examination to assess fetal anatomy and identify any potential abnormalities 2, 3, 4, 5, 6
• Invasive prenatal testing, such as amniocentesis or chorionic villus sampling, to diagnose genetic or chromosomal abnormalities 3, 4, 5, 6
• Maternal blood tests to detect infections, such as parvovirus B19, and to assess for immune causes of hydrops 3, 4, 5
• Fetal echocardiography to evaluate cardiac function and structure 3, 4, 5

Diagnostic Considerations

The diagnostic workup should consider the following potential causes of fetal hydrops:

• Immune hydrops, such as hemolytic disease of the newborn 2, 4
• Non-immune hydrops, including genetic or chromosomal abnormalities, infections, and structural anomalies 3, 4, 5, 6
• Cardiac causes, such as supraventricular tachycardia or congenital heart block 4, 5

Prenatal Management

Prenatal management of fetal hydrops may involve:

• Intrauterine blood transfusions or other interventions to manage anemia or other complications 2, 3
• Thoracentesis or other procedures to drain excess fluid from the fetal thorax or other compartments 2
• Close monitoring of fetal well-being and growth, with regular ultrasound examinations and non-stress tests 2, 3, 6

Prognosis and Outcome

The prognosis and outcome for pregnancies affected by fetal hydrops depend on the underlying cause and gestational age at diagnosis 3, 4, 5, 6.

• In general, the earlier the diagnosis, the poorer the prognosis 6
• The presence of certain underlying conditions, such as chromosomal abnormalities or structural anomalies, may be associated with a higher risk of adverse outcome 3, 4, 6