It involves a blood test and measuring the fluid at the back of the babys neck (nuchal translucency) with an ultrasound scan. This is sometimes called a nuchal translucency scan. The nuchal translucency measurement can be taken during the dating scan.
What is the purpose of a dating ultrasound?
A dating ultrasound gives an accurate estimate of how far along you are in your pregnancy. Many women are uncertain of exactly when conception happened. Ultrasound can tell you how many weeks pregnant you are, based on the size of your fetus.
What do they do at ultrasound appointments?
The ultrasound technician then rubs a transducer wand, which emits sound waves, over the area. The gel conducts the sound waves, which bounce off of the contours of your baby to produce the image youll see on-screen. That image, or sonogram, will be the first picture you have of your baby!