13week scan vs 20 week anatomy scan

Leasha • Mama&wifey 💖

Im super confused! I went to my 13 week ultrasound and they checked for abnormalities including fluid in neck which can detect Down syndrome. Im confused besides the gender what do they check at 20 weeks? Ive had blood work with the 13 week ultrasound also, what im reading is basically everything was already done? Just trying to prep myself on what to expect :)