Even though you may start to feel heavier during week 9, you probably won't look too different. Your uterus is getting much bigger - it is now larger than a grapefruit - so you may notice your waistline starting to expand. Some women are starting to gain weight by week 9, though this may also be related to fluid retention. In other cases, women lose weight if their morning sickness is severe. By week 9, your breasts are also probably larger, though this may not be noticeable.