Umbilical artery thrombosis in pregnancy: risk factors, diagnosis, management, and outcomes

Background: Umbilical artery thrombosis is an uncommon event in pregnancy. Data is limited to case reports and case series. Objectives: The purpose of this review is to examine the etiology, risk factors, incidence, diagnosis, management, and outcomes of pregnancies complicated by umbilical artery thrombosis. Methods: A literature search was undertaken by a university librarian using the search engines PUBMED, Web of Science, Cochrane Database of Systemic Reviews, and Embase. All abstracts/papers were limited to the English language. The search years were January 1980 to July 2024. Search terms included “umbilical artery” OR “single umbilical artery” OR “umbilical arteries” AND “thrombosis” OR “thrombose” OR thrombosing” AND “risk(s) factors” OR “pregnancy” OR “pregnancy complications”. Results: Of the 168 abstracts identified, 49 are the basis of this review. The risk factors were cord abnormalities as well as maternal and fetal diseases. Several adverse outcomes have been reported with umbilical artery thrombosis, including higher rates of cesarean delivery, fetal growth restriction, and intrauterine fetal demise. Conclusions: An umbilical artery thrombosis (UAT) is a rare, but significant pregnancy complication that can lead to unfavorable outcomes. Vigilance is needed when caring for patients at highest risk, as timely identification of UAT may improve pregnancy outcomes.