It is not uncommon for women to discover a smaller gestational age during an ultrasound than they initially anticipated. There can be several reasons for this discrepancy. Firstly, miscalculations in estimating the date of conception or the start of the last menstrual period can lead to incorrect expectations about how far along one is in their pregnancy. Additionally, variations in individual growth rates and development milestones can also contribute to differences between expected and actual gestational ages. It's important to remember that every pregnancy is unique, and these variations are generally considered normal. If you have any concerns or questions about your specific situation, it is always best to consult with your healthcare provider who can provide personalized guidance and reassurance.