Pregnancy dating scans how accurate

Doc says it is likely because the baby is measuring longer than normal.

These measurements are computed automatically in the ultrasound machine’s software.The software has certain measurement scales based on data from large populations, and your baby’s measurements are put into this scale.In other words, by comparing your baby’s measurements to the data from this large collection of measurements, the ultrasound can then tell how far along your baby is. Whatever the reason, an early dating scan can give you peace of mind that all is. outside at your visits but this scan give us a much more accurate idea about the babys growth.