Nausea isn't the only culprit. Dr. Ellis says, "Women who are thin often have to work harder to gain the weight. Sometimes they exercise and need to eat for both the exercise and the pregnancy. At times they just have higher metabolic rates."
Melanie Nicsinger of Overland Park, Kansas, has always been a size three. "It's hard for me to gain weight even if I try, and pregnancy was no exception," she says. By her twentieth week of pregnancy, she had gained nothing, although her doctor wanted her to gain at least 28 pounds and possibly as much as 35. "I definitely think it is possible that women who are naturally thin can experience trouble putting on pounds." Johnson concurs with this thinking. "Sometimes it is simply in the woman's genes not to gain much weight during pregnancy."
Eight million people in the US experience eating disorders, so many women come to pregnancy having either overcome an eating disorder or while they are still struggling with one. Dr. Ellis recommends being open with your healthcare providers about eating disorders. "I very frankly discuss with [women] at the first visit that we will be focusing on her weight at each visit." She recommends that women who have had eating disorders see a registered dietitian and a mental health provider if they think they will feel the urge to diet or purge during pregnancy.
If your healthcare provider is not worried about your lack of weight gain, you shouldn't be either. When you know you're doing everything you can to have a healthy baby, it doesn't matter what others think or say. Nicsinger remembers hearing a lot of comments about how she was too thin and speculation about how great it would be to see her bigger. "People think they can make comments about how you look when you're thin. I just wish people would realize that no one wants to hear that they're 'too' anything, especially when you're pregnant."
Dr. Ellis agrees with this point of view. "Women need to be encouraged to embrace their pregnant and post-pregnancy bodies and give themselves the gift of love, care, and forgiveness. Society needs to support women during pregnancy and not hold women to impossible, unreachable weight standards."