ABSTRACT
This chapter summarizes the role of first trimester sonography in the diagnosis and prognosis of pregnancy. The early pregnancy scan is an essential part of contemporary routine antenatal care. In patients with recurrent pregnancy loss, a normal early pregnancy scan can be highly reassuring. The criteria for diagnosing a nonviable pregnancy or miscarriage by ultrasound has been under constant debate. The predictive value of secondary yolk sac measurements in determining the outcome of an early pregnancy is limited. Fetal heart activity is the earliest proof of a viable pregnancy and it has been documented in utero by transvaginal sonography as early as 36 days’ menstrual age. N. Stamatopoulos et al. attempted to develop and test a prediction model to assess the risk of subsequent pregnancy failure among women who are diagnosed to have a viable intrauterine pregnancy using an early pregnancy scan.
