surprise spotting

[eatswithfork]

Hi everyone! So my body has been a bit wonky lately and I've been graced with surprise spotting (boo). My body seems to know which nights I'm not wearing a pad or liner just in case and starts up the works. There really is no pattern to it and I really don't want to wear liners round the clock all the month through so for the sake of my mattress, I wanted to ask if my idea would work. I know very few of us use wool pads, but it kind of goes off that idea so I'm hoping someone has some advice about this :)

My idea is to get a military surplus wool blanket to lay over my mattress under my sheet so that I'm left with only washable things that are stained rather than a cumbersome thick mattress pad and heaven forbid the actual mattress. Would that actually act as a barrier? I would have to lanolize it I imagine but would I have to felt it too? I'd rather have the full size :/

As far as the obvious solution of waterproof mattress pad goes, I'm looking for the more natural fiber route and I already have a mattress pad I like :)

Sorry this is a tad off the topic of pads but I thought I could find help here :) Thanks a million!!

Edit: or would fleece be better? not a natural fiber either but at least it would lie flat rather than being another fitted thing on my bed.