I have a ball I bought, I sat on it yesterday only for 10 minutes and spent the rest of the evening with back and hip pain, all I did was sit on it and watch tv!.
am I supposed to be doign something special with it - surely its not supposed to leave you felling like you lower half is abotu to explode? do I need to wait until I am further along (I am 37 weeks now) or shall i just give it to the kids to play with instead?