RESUMO
Background & Objective: As the technology used in sonography has become more advanced accurate estimation of gestational age (GA) has become more demanding to plan treatments in pregnancy. Fetal kidney length (FKL) alone or its combination with other biometric parameters can be used in GA calculation more precisely in IInd&IIIrd trimester. Methodology: Two hundred three healthy pregnant females of IInd&IIIrd trimester were analyzed for GA calculation via FKL, Bi parietal diameter (BPD) and femur length (FL) using various lenear regression models. Results: Fetal kidney could be seen easily sonographically at 16thwk of gestation. FL was the most accurate single parameter (SE + 7.95 days) followed by FKL + 9.56days; BPD was the least accurate + 9.86 days. GA can be calculated most accurately by combining FKL with FL and BPD with SE + 7.12 days. Conclusion: FKL is easy to measure in IInd and IIIrd trimester and more accurate than BPD for GA estimation. So FKL could be used alone or easily incorporated into the model for dating pregnancies after 16th wk of gestation, in particular when measurements of BPD and FL are difficult.