Key parameters to asses the health of the baby is its weight gain. Fetal weight development is measured after every ultrasound during pregnancy. During the first 8 weeks, the fetus is too small to be weighed. The first few weeks the fetal heartbeat and rate is monitored. From 8 weeks to 20 weeks, babies are measured from head to the bottom as their legs are still curled. After that, babies are measured from head to toe. During the scan, the radiologist will make a few measurements of the fetus like the - Biparietal diameter (BPD) which measures the baby’s head from side to side, Femur length (FL)-measuring the thigh bone length, Head circumference(HC), Occipitofrontal diameter(OFD)- the length from the root of the nose to frontal bone's most prominent point, Abdominal circumference(AC)-