So... I was already taking 100 mg B6 because I had shortish luteal phases and then (just before conceiving this PG) an earlyish m/c that I suspected had to do with low progesterone. I just continued to take my B6 after my BFP because of this issue (though my 5 week progesterone numbers were decent).
It's highly unscientific, but I'd guess I had less m/s than the average woman and it was shorter in duration. Certainly milder than anyone in my family (that I know of). My m/s went like this: I had nausea, at first in the morning and eventually all day, but NEVER once threw up and never even felt like "I'm right about to throw up." It was still super-annoying at times, made me feel "yucky" and I didn't feel like eating anything but noodles, but in the scheme of things, I think relatively mild. It lasted from 5.5 weeks to yesterday (11.5 weeks), but really started tapering at 10.5 weeks. Hopefully it's over now.
...I say all this because I assume the B6 I was taking anyway had a lot to do with my "reasonable" m/s. Since this pregnancy seems super-sticky and my m/s seems to be over, I will probably taper off the B6 within the next week.
Hope that helps!