Am 36 weeks and friends have started making jokes about getting a tarp out for the sofa when I visit. These are friends who have had babies. When is a good time to start to protect things like the sofa, matress, car etc in case of waters breaking in a gush? And what should you use? I have seen maternity pads in Boots/Mothercare but you would just roll/wriggle off them at night wouldnt you?