Assertion: umbilical cord's artery | /r/HasProperty | rare
Facets:
value: in normal fetuses
type: OTHER
value: very
type: DEGREE
Source sentences:
text: Replaced umbilical artery to the superior mesenteric artery is very rare in normal fetuses (some may be trisomy 21) but it is common fetuses with defective vascularization (fetus-in-fetu57, acardiac twins and sirenomelia fetuses58,59).