I'm a big fan of food logging and have kept a pretty detailed one for the past six years, including a weekly weigh-in. During pregnancy, I knew I would need extra calories, but I wanted to make sure they were coming from a nutrient dense food sources. I added 300 calories to my daily caloric goal, and did my best stay in range throughout my pregnancy. At the end of the week, I would take a few minutes and review my nutritional data, see if I was lacking on any major nutrients, and make a plan on how to do better the following week. Keeping track of my calories has always been one of my most important tools for maintaining a healthy BMI, and I found it to be just as effective during pregnancy.