Bathsheba - yes I am very interested to see how much of the weight will disappear while breastfeeding. I'd say probably a lot. My mother always says "It helps to have something in reserve!"

Thanks everyone for your input. Since I've first posted, the gain has slowed and I think it's now just Willmartin who is gaining at a rapid rate. In any case, I only have two weeks of work left so who cares if the mat clothes don't fit after that!