At 32 weeks a baby weighing around 1.8 kg (about 4 pounds) is within the normal range. In my pregnancies the growth scan estimates varied by a few hundred grams and each of my babies grew at their own pace. What matters most is the overall growth trend and how active your little one is, not the exact number from a single scan. Keep eating well, stay hydrated and rest when you can. Your care team will let you know if there is any reason to be concerned, but many mums deliver perfectly healthy babies who are a bit smaller or larger than average.