Change:  EFW or greater than 20mm difference in AC)If monochorionic pregnancy or Twin-Twin Transfusion Syndrome is suspectedPerform a more detailed assessmentOther ultrasound scanning guidelines for pregnancy1st Trimester2nd Trimester - Morphology3rd Trimester ....Go back to ultrasound protocols homepage   View changes from previous version. (Word count: 107)

Change: Relative size of amniotic sac volumes (deepest pool or two quadrant AFI)Relative size of twins (significant discrepancy is 20% difference in EFW or greater than 20mm difference in AC)If monochorionic pregnancy or Twin-Twin Transfusion Syndrome is suspectedPerform a more detailed assessment ....Go back to ultrasound protocols homepage   View changes from previous version. (Word count: 94)