I'm 23 years old. I'm 5'10 and ( I lift weights so I have more muscle then fat ) I way about 140. ( which is underweight for my height and age bmi) I've always been Victoria secret model thin. But me and my husband have been trying for a baby and I believe that might be what's about to happen. I'm concerned about the weight gain ladies get while pregnant. Question is if your in your early 20s always no matter what been skinny ( eat a whatever I want. ) what are the chances that I would gain weight. Does it have to do with what you eat?