Does one need to gain extra weight if pregnant with multiples?

"In general the weight gain will be little minimal or sometimes it may be even there may weight loss in the first trimester because of the excess vomiting and the less intake of the food. But subsequently what happens is there will be a good weight gain, roughly about 2 kgs every month or half kg per week This is the standard weight gain for singleton pregnancy. But in multiple pregnancy, weight gain may be a little more than that because of the extra retention of the water in the mother, increased blood volume in the mother and because of the two fetuses where which both babies contribute to the weight of the mother"