I've learned that it's down to the kind of weight you put on, not how much. If you eat healthily throughout your pregnancy then there's a greater chance for healthy weight gain and instant weight loss upon delivery and recovery. Unfortunately there is little rhyme nor reason for the amount each of us gains, it is entirely individual. But those who lose it quickest are those who continue to exercise and eat well. During the first trimester eat at maintenance, add calories during the second and third trimesters as necessary. MFP should be able to calculate what your maintenance should be if you enter the correct information into the settings. Congratulations and good luck!