Screening for Down's syndrome will happen at the dating scan if:. What will I learn from a dating scan? It is also impossible to do a thorough foetal screening assessment because it is still just too premature in terms of embryonic development. Take a look at each week of your pregnancy, from conception to birth, with our comprehensive email newsletters. In some situations, such as when the scan is completed before 10 weeks of gestation or you are overweight, you may also need a vaginal scan.
In some respects the seven week ultrasound can be quite accurate because the embryo is developing very quickly.
7 Week Ultrasound
If you choose to have a dating scan, it will most probably be your first scan. It involves a blood test and measuring the fluid at the back of the baby's neck nuchal translucency with an ultrasound scan. Gender Don't know yet Boy Girl. This is because although every little embryo is unique, there are still defining characteristics of development which apply to all embryos at particular stages of early gestational development. The limbs and the yolk sac, though obviously important, are not the primary means of measuring growth.