Yes, you can! As a matter of fact, we will introduce a pregnancy mode further down the line. It will not be available at the time of the release.
For now, you will be able to see the visual evolution of your body with the Difference View, Heatmapping features and body measurement data (body fat %, lean mass, muscle measurements) but not for the belly area.
It will be approximatively a year from the ShapeScale release to collect data and introduce the pregnancy mode for better belly area fat tracking.