Advancement in TVS has revolutionized the management of early pregnancy. Care providers can utilize this noninvasive tool for a better understanding of the embryonic development and thus improve their clinical as well as counselling skills. This chapter discusses in detail the embryonic developmental features, application of TVS in management of early pregnancy failure, ectopic pregnancy and multiple pregnancies, placental pathologies on USG, identification and evaluation in first trimester markers of aneuploidy, 3D and 4D USG in first trimester, and markers for Preeclampsia through TVS in early pregnancy. The sonographic images have been very well placed in the chapter for the better understanding of the readers.