A baseline blood and urine test. Once your urine pregnancy test is positive, it is best to get an ultrasound done 2-3 weeks after the missed menstruation. This ultrasound can confirm the well being of the pregnancy. It also provides an accurate EDD, the Expected Date of Delivery. The EDD is the 40th week of your pregnancy. It is an important date as the entire roadmap for the pregnancy is based on this EDD date. The EDD is most accurately determined at 8-12 weeks of pregnancy.