Accuracy of Fetal Foot Length Measurement in Estimation of Gestational Age and Fetal Weight in the Third Trimester of Pregnancy

Abstract

Background: Fetal foot length (FFL) is a biometric parameter that has been established for estimating the gestational age (GA). Accurate knowledge of fetal weight (FW) and GA assist Clinicians in the evaluation of fetal growth and predict neonatal outcomes. Aims: This study aims to predict the estimated FW and GA using the FFL in 26–40 weeks’ gestation on antenatal ultrasound. Materials and Methods: In a retrospective study, we investigated the fetal measurements of FFL, femoral length (FL), and estimated FW in 100 pregnant women at 26–16 weeks’ gestation who attended routine antenatal care. The fetal measurements were examined about the foot length. Results: The foot length was not a significance parameter to determine fetal gender (P = 0.6). There was no correlation of FFL with maternal socioeconomic status, parity, fetal gender, and maternal body mass index, P = 0.26, 0.84, 0.67, and 0.26, respectively. The FFL, FL, and estimated FW were strongly and linearly correlated with GA. The combination of FL, foot length, and estimated FW provide an accurate estimation of GA with minimum (standard error [SE] = 1.75). The combination of FL and foot length provide an accurate prediction of FW with SE of 320.52. The foot length and FL revealed similar values of SEs in estimated FW (R2 = 0.85) for each. Conclusions: The FFL is linearly correlated with GA, FW, and FL. It is an accurate parameter to assess the GA and reliable for predicting the estimated FW. This is useful for assessing fetal growth and skeletal dysplasia.