Sometimes the body just messes up, though. As Marie says, think about crooked teeth, or spina bifida, or chiari malformation (where the opening for the brainstem is too small.) There are all sorts of things that can go wrong in utero. And having a compromised venous return or a venous malformation is congenital. We ain't perfect, but we're built to heal. Many congenital conditions can be helped by surgery and modern medicine...braces for the teeth, stents for the veins.
Husband dx RRMS 3/07
dx dual jugular vein stenosis (CCSVI) 4/09