Down syndrome markers

Alissa

Hi all, I’m 33 weeks currently and at a growth ultrasound last week we found out our baby has some soft markers for DS. Overall she’s at the 20th percentile for weight at 4.2lbs. Her femur is measuring 3 weeks behind in the 2nd percentile, her head is 2 weeks behind in the 6th percentile and her abdomen is a few days ahead at the 56th percentile. The doctor mentioned a possibility of DS (dear son) even though we did the Harmony screening in the first trimester and received low risk assesment. Did any of you have similar measurements with femur and head lagging behind abdomen? I haven’t heard of those as being Downs markers before. The doctor offered amniocentesis but I declined given she has no heart defects or anything like that. Any advice welcome.