Ultrasound Biometry of Nigerian Fetuses: 1. Estimated Fetal Weight

Fetal weight studies are few in Nigeria and the population used for these studies are too small to provide a meaningful statistical significant data for the relationship between it and age. In the developed countries, fetal weight reference values have been produced but there are no such in our environment. This study was designed to establish chart of fetal weight in Jos. A total of 12,080 pregnant women were scanned in a cross-sectional study at the Centre for Reproductive Health Research, Jos over a period of five years. The mean estimated weights and percentiles of 12,080 fetuses from 17-42 weeks are presented in a tabular form. Mathematical modeling of data demonstrated that the best-fitted regression model to describe the relationship between estimated fetal weight and gestational age was the power regression equation y = 0.038x3.1347 where y is the fetal weight in grams and x is the fetal age in weeks with a correlation of determination R2 = 0.9951 (p< 0.001). When fetal weight was plotted against symphysio-fundal height, it was found out that there is a positive correlation between fetal weight and symphysio-fundal height with a correlation of determination R2 = 0.9951 (p< 0.001). The relationship is best described by the power regression equation y = 0.0409x3.1217 where y is the fetal weight in grams and x is the symphysio-fundal height in centimeters. It is concluded that the estimated weight of fetuses in Jos correlated well with gestational age and symphysio-fundal height.