Assessment of Mean Fetal Kidney Length as a Reliable Parameter for Accurate Estimation of Gestational Age in Late 2nd and 3rd Trimesters

Inclusion Criteria: * All healthy women with viable normal singleton pregnancies in their late second and third trimesters (24 weeks - 40 weeks) calculated from their last menstrual period. * Women who will sure of the dates of their last menstrual period (1st day) and/or those with first obstetrics dating using crown rump length (CRL). 3- Women with regular menstrual cycle in last three months before their last menstrual period. Exclusion Criteria: * Women with high-risk pregnancies such as preeclampsia, diabetes, hypertension, polyhydramnios. ❖ Maternal: * Multiple pregnancies. * Gross maternal obesity. ❖ Fetal: * Fetus with congenital anomalies especially renal anomalies. * Fetuses with abnormal renal morphology (a genesis, hypoplasia, cysts, nephromegaly, polycystic kidney, hydronephrosis, etc.… * Fetuses with renal pelvic dilatation of 5 mm or greater, obscured adrenal and renal border. * Fetus with growth abnormalities (intrauterine growth retardation or macrosomia).