Macrosomia can be defined as birth weight equal to or exceeding 4000gm. The etiology of fetal macrosomia is believed to be multifactorial. Fetal macrosomia has an important impact on both fetus and mother. Maternal complications include arrest disorders, protraction disorders, and instrumental delivery with more obstetric lacerations, post partum hemorrhage, puerperal infections, cesarean delivery and shoulder dystocia. Fetal complications include birth injuries, asphyxial injuries, neonatal hypoglycemia as well as childhood and adolescent obesity. Accurate prenatal diagnosis of macrosomia is important for planning and timing of the method of delivery. Diagnosis can be done through risk assessment, clinical estimation of fetal weight and Ultrasonography. Preventive factors of fetal macrosomia include reduction of pre-pregnancy weight and weight gain during pregnancy, limitation of post term pregnancy and control of diabetes. The management of patients with suspected fetal macrosomia is controversial. Elective cesarean delivery and labor induction have been proposed as interventions to prevent maternal and perinatal complications.