English abstract
Objective: Little published research exists in the area of fetal thigh biometry, specifically in the use of the anterior posterior fetal thigh diameter (APTD). A continuing review of existing practices needs to be coupled with evaluation of alternate or
additional methodology. This study evaluated the usefulness and direct correlation of a simple, new method of predicting fetal age
by measurement of the anterior-posterior thigh diameter (APTD) in a normal 8-to 28 week pregnancies using two-dimensional
sonography. Methods: This was a quantitative prospective study of 55 patients in the High Level General Hospital, Alberta, Canada.
Anterior-posterior thigh diameters (APTD) were sonographically measured and the normal range for each week of pregnancy was
determined five times for reliability. Results: Significant correlation was found between (APTD) and fetal age from simple line regres sion analysis, with >99.9% confidence intervals at each week from 8 to 28 weeks gestation. There was a correlation of mm APTD
per week of fetal age. The standard error of estimation was very low at (0.08664) in edition (r>0.9993) and (p < than 0.000). The
residual scatter plots confirmed the APTD validity. Conclusion: APTD is a reliable and valid method for assessing fetal age in a normal
pregnancy and may be particularly useful when other parameters are unable accurately to predict fetal age. An accurate linear meas urement of multiple fetal parameters allows a more complete profile of fetal growth and estimated date of delivery (EDD). APTD may
also be useful in identifying fetal growth problems. All of the values of fetal age lie directly on the "best-fit" regression line. Since the
coefficient of determination (Rsq) is very high, this model is very effective
