BMI from 25-30 shouldn't gain more than 25 pounds. You don't HAVE to gain the maximum you are allowed to. My OBGYN said I could eat more if I wanted to as I was on the slender side to begin with (BMI 18)  but since the baby has been measuring exactly right at every point there's no need to eat a tonne more. If the baby is healthy and she's not facing imminent famine conditions WTF.