median sacral vein
Go to external page
http://purl.obolibrary.org/obo/UBERON_0006687
The median sacral vein (or middle sacral veins) accompany the corresponding artery along the front of the sacrum, and join to form a single vein, which ends in the left common iliac vein; sometimes in the angle of junction of the two iliac veins. [ http://en.wikipedia.org/wiki/Median_sacral_vein ]