I don't have any reference for you but only personal experience. My sx seemed to be holding steady while on the pill. When I was off it for a couple years I had horrible, waves of flaring sx that lasted nearly a year.

I went back on the pill last summer and seem to have stabilized, although there is residual permanent (sensory) sx hanging around still. My neuro didn't see a connection, and it may be coincidence only. I just don't want to take a chance it's not related and stop the pill to find out.

If anyone has more info, I'd be interested too.