Dating and Viability scan between 6 and 9 weeks..to tell Date of delivery n if dere is viable(live) fetus Nuchal translucency scan sometimes called the early morphology scan between 11 and 13 weeks..to rule out down syndrome Anomaly scan between 18 and 20 weeks..to knw baby has grown prperly growth scan or fetal wellbeing scan between 28 and 32 weeks. Growth scan and color Doppler studies between 36 and 40 weeks