Establishing Fetal Weight Standards in North Indian Population

Objective: To create a reference chart for estimated fetal weight (EFW) in normal pregnancy for use in North Indian population and compare it with reference chart with western population. Single reference standard charts that were developed for the western population are being followed worldwide despite many differences between the populations in terms of genetics, nutrition, cultural practices, socio-economic status, and environmental factors. These factors can affect the fetal weight and using same reference can lead to a risk of over diagnosis of growth restriction in some populations. Fetal weight is an important clue when it comes to the assessment to growth of the fetus. This study is an attempt to provide reference values for the targeted north Indian population. We included 2433 normal singleton pregnancies coming for routine antenatal ultrasonography examination at our institute. Ultra-sonographic measurements included fetal biparietal diameter (cm), head circumference (cm), abdominal circumference (cm) and femur length (cm). Estimated fetal weight (gm) was calculated by using Hadlock algorithm. These values thus obtained were recorded, tabulated and centiles (10th, 50th, 90th, 95th and 97th) were derived from this data. It was then compared with western population reference. Estimated fetal weight was found to be at lower range in Indian population compared to western population.