I am also pregnant with triplets....2 of them are measuring the same, and the other one is measuring about 4 days later. Do you know if your friends triplets are all in their own sacs? All of mine are seperate, which means that the 3rd one was probably fertilized at a different time. If some of them/all of them are sharing the same sac, then 1 might not be getting as many nutrients, like imreddy said.View Thread