Hi, I got my nt scan done on 8th aug(results are normal) and double marker on 12th aug( shows low risk for trisomies) 1) Is it ok if there is a 3 to 4 days  gap between nt and double marker test? Will it alter the accuracy? 2) How valid is double marker test for a DCDA twin pregnancy 3)I am on Susten 1-0-1 and duphaston 1-1-1 , will this alter  hcg levels and affect the double marker test? 4)Report says beta hcg is high. Is 194 ng/mL beta hcg high for a DCDA twin pregnancy? What is the normal range? 5) Should I worry about beta hcg if trisomies risks are low? I have attached the report for analysis. Please guide if the results are fine . Thank you.