Association of Isolated Single Umbilical Artery with Maternal Health and Placental Pathology; a Retrospective Study of over 6,500 Placentas
Amanda Treece, Stephanie Reilly, Ona Faye-Petersen. University of Alabama, Birmingham, Birmingham, AL
Background: While single umbilical artery (SUA) has an overall incidence of 1%, isolated SUA (iSUA) occurs in only 0.37-0.5% of pregnancies. Isolated SUA is independently associated with fetal intrauterine growth restriction (IUGR), prematurity, multiple gestations, and maternal chronic (CHTN) or gestational hypertension (GH) and diabetes mellitus (DM). It is of questionable clinical significance in the newborn period and has not been associated with long term, adverse growth and neurologic outcomes. However, we queried whether noninfectious placental pathologies seen with CHTN, GH, DM, and placental dysfunction, and/or those fetal conditions linked to adult onset cardiovascular and chronic renal diseases were more common with iSUA.
Design: A retrospective review of all institutional placental and previable fetoplacental (gestational age <20 wk) surgical pathology accessions from 1/01/2006 to 12/31/2010 was undertaken. Patient demographics, obstetrical history and pathologic diagnoses were extracted from the medical records.
Results: There were 6534 cases with evaluable umbilical cords. Overall incidences of SUA and iSUA were 3.2% (n=211) and 1.9% (n=110) respectively, with iSUA significantly associated with multiple births (p=0.011), CHTN (p=0.0270), GH (p=0.032), DM (p=0.023), IUGR (p=<.002), low placental weight (p=<.002), and non-central cord insertion (p=0.001) compared to normal cords. Chronic chorionic villous (CV) ischemia was significantly more common in singleton placentas with iSUA versus 3-vessel cord cases (p=0.024); CV infarction was more frequent, but the difference was not significant (19.4% versus 14.4%, p=0.178). In singletons with non-central cord insertion and CHTN, DM, and/or GH, 82.4% of iSUA cases had CV ischemia versus 65.0% with 3-vessel cords (p=0.249). No association with prematurity, fetal thrombotic vasculopathy (FTV), or villitis of unknown etiology (VUE) was found.
Conclusions: We confirmed the association of iSUA with IUGR, multiple birth, CHTN, DM, and GH. We found significant independent association between iSUA and chronic CV ischemia and an increased rate of CV infarction; however, no significant association was found for preterm birth, FTV or VUE. The higher rate of CV ischemia after controlling for insertion site and CHTN, GH, and DM suggests that iSUA cord placentas may be more susceptible to ischemia than 3-vessel cord placentas. The higher association with CV infarction did not reach statistical significance, possibly due to sampling.
Category: Gynecologic & Obstetrics
Wednesday, March 21, 2012 9:30 AM
Poster Session V # 159, Wednesday Morning