Nuchal fold on ultrasound

So i got a call from my doctor and she said my baby boy looks healthy and heart looks good he is 12oz and she thinks baby is looking good...she did mention that he has nuchal fold above the measurement then call normal...has any one had experience with this before.. she referred me to fetal medicine to have a level 2 ultrasound done to make sure there everything is fine.but she said she doesnt want me to stress because she is not concerned about anything being wrong...any advice or stories would help me keep at ease..thank you