Double markers test is indicated to screen for trisomies in the first trimester, but not routinely done as NT is sensitive enough with experienced radiologist/gynaecologist. There are some tests can be done in the 2nd trimester as well. How many weeks are you in the pregnancy? You can talk about it with you gynaecologist if you want those tests to be done

For full guidance, prescription and follow up take a paid instant consultation. Hope that helps. You can even video consult directly via what sapp on 9999x104x408