CLINICAL TOOL
Fetal Doppler Reference Guide & Centiles
Clinical reference guide for interpreting UA, MCA, DV, and uterine-artery Doppler measurements and centile concepts by gestational age.
About this page
This is a clinician-reviewed evidence brief, not an interactive calculator. It summarises the guideline logic our subspecialists apply when managing these cases every day. For a case-specific assessment, request a consultation or refer your patient.
Clinical Purpose
To support interpretation of fetal-placental Doppler measurements, including MCA-PSV assessment for fetal anaemia and UA/MCA/DV assessment in fetal growth restriction. This page is a reference guide, not a numerical calculator.
Inputs
- Gestational Age (Weeks + Days)
- Umbilical Artery (UA) PI/RI
- Middle Cerebral Artery (MCA) PI/PSV
- Ductus Venosus (DV) PI
- Uterine Artery (UtA) PI
Formula & Guideline Source
ISUOG Practice Guidelines on Doppler Ultrasound, Nicolaides et al. (Fetal Medicine Foundation), Mari et al. (MCA-PSV).
Limitations
Doppler indices are technique- and angle-dependent, especially PSV. This guide does not calculate a patient-specific centile. Clinical management requires integration with biometry, fluid, CTG, gestation, and the full clinical context.
FAQ
When is MCA-PSV indicated?
MCA-PSV is primarily used to screen for fetal anemia (e.g., in alloimmunization or parvovirus infection) usually up to 35 weeks. Values >1.5 MoM are indicative of moderate to severe anemia.
What does an absent end-diastolic flow (AEDF) in the Umbilical Artery mean?
AEDF indicates significantly increased placental vascular resistance and is a sign of advanced fetal compromise in the setting of FGR, necessitating intensive surveillance and usually delivery if beyond 32-34 weeks.
References
- ISUOG Practice Guidelines: use of Doppler ultrasonography in obstetrics. Ultrasound Obstet Gynecol. 2013.
- Mari G, et al. Noninvasive diagnosis by Doppler ultrasonography of fetal anemia due to maternal red-cell alloimmunization. N Engl J Med. 2000.