Molecular biology of the placenta is a fascinating research subject to investigate the mechanisms underlying fetal growth abnormalities and developmental disorders. Analysis of Placental Gene Expression Profile in Abnormal Fetal Growth provides a new insight into the gene dysregulation and pathway changes in the placenta of pregnancies affected by fetal growth restriction and macrosomia. This book reviews the physiology of the placenta and its divers roles in maintaining a healthy fetal development. There is a summary of the aetiology of abnormal fetal growth and its adverse effects on the future of infants. The main focus of this book is presenting the findings achieved by microarray gene expression analysis in the placentas collected from growth restricted and macrosomic newborns, introducing some candidate genes for screening purposes. In addition, molecular function of dysregulated genes and affected biological pathways have been described in detail.