Generally the common weight gain in pregnancy is 25-30 lbs. Some women gain much more than that and some (myself) hardly gain at all. 25-35 lbs is the median and recommended weight gain in the average pregnancy. If the mother is a larger stature, the weight gain will go down to 20-25 lbs.
my dr told me 25-30 lbs but Ive gained 33 (i was skinny when i got preg lol) and all my weight gain is all baby (Ive been watching). My dr told me though that my son is a bit bigger then what their used to but she can see why bc I was a big baby and so was my hubby.