Pregnancy: Possible signs of Chiari?

I havn't been tested for Chiari yet but some things during my pregnancy make me wonder if anyone has had these same problems who have Chiari.

Increased migraines - even with prescription meds wouldnt help....I noticed an increase in how many optical migraines I would get compaired to not being pregnant where my vision would be spotty. It was about every 2 wks compared to every 3months.

PVB - premature ventricular beats, whenever my pulse would get up around 100 I would have an extra beat....I had this with both pregnancies and it went away after

Numbness in lower legs - sometimes my shins and calves would go numb after walking for awhile.....this could also be attribruted to me carrying twins

Severe siatic pain - I had a lot of problems with my siatic nerve in my sides hurting

and with both pregnancies even though I got the epidural I was still able to feel lower sensation and pain, I got it about 2-3hrs before each birth they had even given me an extra dose and after my daughter I was able to walk, but after my sons they forgot it on for another hr and I couldnt....seems a little strange that it took 5hrs for the epiddural to acheive full effect, and about 2hrs after the epidural with my sons I was still able to use my leg muscles to move from bed to bed.