This topic can be a source of confusion and anxiety to many providers of OB care, and we hope that we can at least provide some of the basics in today’s episode. For in depth review, see ACOG PB 163 for screening tests, and PB 162 for prenatal testing (ACOG membership required).
One of the most useful and high yield tables on this subject is Table 2 from PB 163 (below). Knowing the differences between these tests, their components, and advantages/disadvantages can be useful for exams as well as your clinical practice.
PB 163 also reviews what the workup should be after a positive screen or after a sonographic finding of aneuploidy, which we did not cover in totality on today’s episode but may also be of use to you.
Just remember — are you screening, or are you testing?