Absent umbilical arterial end-diastolic flow
Citation, DOI & article data
Absent end-diastolic flow (AEDF) in an umbilical artery Doppler assessment is a useful feature which indicates underlying fetal vascular stress if detected in mid or late pregnancy. It is often classified as Class II in severity in abnormal umbilical arterial Dopplers 9.
The presence of absent end-diastolic flow (AEDF) can be normal in early pregnancy (up to 16 weeks). In mid to late pregnancy it usually occurs as a result of placental insufficiency 7,8. Flow in the umbilical artery should be in the forward direction in normal circumstances. If placental resistance increases, the diastolic flow may reduce, later becoming absent and finally reverses.
- intra-uterine growth restriction (IUGR)
- increased risk of neonatal thrombocytopenia 6
- increased risk of necrotizing enterocolitis1
The umbilical arterial velocity is seen reducing to zero at end diastole. The impedance is found to be highest at the fetal end of the umbilical cord and therefore the absence of end diastolic flow is seen first in this region.
Treatment and prognosis
The situation is associated with an increased risk of fetal and neonatal mortality, as well as an increased incidence of long-term permanent neurologic damage 5.
Approximately 1/3 of cases may improve with bed rest. Often it is recommended that close follow-up or expeditious delivery be pursued 7.
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- 2. Rochelson B. The clinical significance of absent end-diastolic velocity in the umbilical artery waveforms. Clin Obstet Gynecol. 1989;32 (4): 692-702. - Pubmed citation
- 3. Forouzan I. Absence of end-diastolic flow velocity in the umbilical artery: a review. Obstet Gynecol Surv. 1995;50 (3): 219-27. Obstet Gynecol Surv (link) - Pubmed citation
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- 6. Baschat AA, Gembruch U, Reiss I et-al. Absent umbilical artery end-diastolic velocity in growth-restricted fetuses: a risk factor for neonatal thrombocytopenia. Obstet Gynecol. 2000;96 (2): 162-6. - Pubmed citation
- 7. Wang KG, Chen CY, Chen YY. The effects of absent or reversed end-diastolic umbilical artery Doppler flow velocity. Taiwan J Obstet Gynecol. 2009;48 (3): 225-31. doi:10.1016/S1028-4559(09)60294-1 - Pubmed citation
- 8. Battaglia C, Artini PG, Galli PA et-al. Absent or reversed end-diastolic flow in umbilical artery and severe intrauterine growth retardation. An ominous association. Acta Obstet Gynecol Scand. 1993;72 (3): 167-71. - Pubmed citation
- 9. Gerber S, Hohlfeld P, Viquerat F et-al. Intrauterine growth restriction and absent or reverse end-diastolic blood flow in umbilical artery (Doppler class II or III): A retrospective study of short- and long-term fetal morbidity and mortality. Eur. J. Obstet. Gynecol. Reprod. Biol. 2006;126 (1): 20-6. doi:10.1016/j.ejogrb.2005.07.008 - Pubmed citation
- 10 .Merz E, Bahlmann F. Ultrasound in obstetrics and gynecology. Thieme Medical Publishers. (2005) ISBN:1588901475. Read it at Google Books - Find it at Amazon