I was pretty cautious about this because of the heat, when I was pregnant.
if you think how a phone interferes with tvs and radios, imagine what that is doing to a baby. but aparently standing infront of microwaves and having a laptop on your lap, it has not been proven to affect baby but to be sure, id rest it on the arm of the chair or a table. if you are unsure about anything, best not to do it :) xo