Uterine artery flow notching
Citation, DOI & article data
Uterine artery flow notching refers to a phenomenon observed in uterine arterial Doppler ultrasound assessment.
The presence of notching after 22 weeks is associated with several other conditions including adverse pregnancy outcomes. These include
- pregnancy induced hypertension (PIH)
- placental abruption
- intrauterine growth restriction (IUGR)
- increased maternal serum alpha fetoprotein (MSAFP)
While notching can be either systolic or diastolic, it is typically seen as a trough-like notch between the systolic and diastolic phases.
The presence of notching in late pregnancy is an indicator of increased uterine vascular resistance and impaired uterine circulation 2.
Bilateral notching is more concerning. Unilateral notching of the uterine artery on the ipsilateral side of the placenta, if the placenta is along one lateral wall (right or left) carries the same significance as bilateral notching. The presence of an early diastolic notch can however be a normal finding in a non-pregnant uterus and even in a gravid uterus, at least up to 16 weeks, but notching typically begins to disappear in the gravid uterus by 13 weeks with clearly established diastolic flow by 20 weeks 7.
- 1. Thaler I, Weiner Z, Itskovitz J. Systolic or diastolic notch in uterine artery blood flow velocity waveforms in hypertensive pregnant patients: relationship to outcome. Obstet Gynecol. 1992;80 (2): 277-82. - Pubmed citation
- 2. Ochi H, Matsubara K, Kusanagi Y et-al. Significance of a diastolic notch in the uterine artery flow velocity waveform induced by uterine embolisation in the pregnant ewe. Br J Obstet Gynaecol. 1998;105 (10): 1118-21. - Pubmed citation
- 3. Harrington K, Cooper D, Lees C et-al. Doppler ultrasound of the uterine arteries: the importance of bilateral notching in the prediction of pre-eclampsia, placental abruption or delivery of a small-for-gestational-age baby. Ultrasound Obstet Gynecol. 1996;7 (3): 182-8. doi:10.1046/j.1469-0705.1996.07030182.x - Pubmed citation
- 4. Merz E, Bahlmann F. Ultrasound in obstetrics and gynecology. Thieme Medical Publishers. (2005) ISBN:1588901475. Read it at Google Books - Find it at Amazon
- 5. Maulik D. Doppler ultrasound in obstetrics and gynecology. Springer Verlag. (2005) ISBN:3540230882. Read it at Google Books - Find it at Amazon
- 6. Mires GJ, Williams FL, Leslie J et-al. Assessment of uterine arterial notching as a screening test for adverse pregnancy outcome. Am. J. Obstet. Gynecol. 1998;179 (5): 1317-23. - Pubmed citation
- 7. Kennedy AM, Woodward PJ. A Radiologist's Guide to the Performance and Interpretation of Obstetric Doppler US. (2019) Radiographics : a review publication of the Radiological Society of North America, Inc. 39 (3): 893-910. doi:10.1148/rg.2019180152 - Pubmed