Sildenafil Versus Low Molecular Weight Heparin in Fetal Growth Restriction Treatment

Inclusion Criteria: * Maternal age between 20-35 years. * Being at a gestational age 28-35wks. * Singleton pregnancy. * Fetal growth restriction diagnosed by ultrasound with estimated fetal weight below the 10th percentile, and/or fetal abdominal circumference at or below the tenth percentile. Exclusion Criteria: * Maternal age less than 20 years or more than 35 years. * Undetermined gestational age. * Multiple gestation. * Chronic diseases with pregnancy e.g. Chronic hypertension, diabetes type 1 or 2. * Etiologies of FGR other than placental insufficiency as fetal malformations, aneuploidy or infections. * Suspected fetal compromise requiring emergency delivery. * Any contraindication to the use of sildenafil e.g. known significant maternal cardiac disease, left ventricular outflow tract obstruction, concomitant treatment with nitrates or previous allergy to sildenafil. * Any contraindication to the use of LMWH e.g. known bleeding disorder, active antenatal bleeding or at increased risk of major hemorrhage (e.g. placenta praevia), thrombocytopenia, severe renal or hepatic disease. * Drug or alcohol abuse. * Patient refusing to participate in the study or unable to consent.