umbilical artery
Medical/anatomical term for the paired arteries that carry deoxygenated blood from the fetus to the placenta.
The umbilical artery is one of the blood vessels connecting the fetus and the placenta.
臍静脈 (umbilical vein) carries oxygenated blood from the placenta to the fetus, opposite to the umbilical artery.
Compound of 臍 (さい, 'navel') + 動脈 (どうみゃく, 'artery'). The reading さい for 臍 is the on'yomi used in medical compounds.