Can the routine fetal anatomy ultrasound be performed earlier than the standard 18-20 weeks? is 15-16 weeks way too early to have this done?

Yes BUT: Depends on the size of the mother for one. An obese mother will be a more difficult patient to get a good sono especially early. At 15-16 weeks it is possible to do a fairly extensive anatomical survey with evaluation of the brain, face, heart, spine, abdomen, and extremities. The way the fetus is lying is also an important consideration. Depends on the comfort level in your area.

Generally : Some people try to push the envelope on this and you can certainly look at that time and rule in an abnormality but it would be harder to rule out an abnormality. Best time is between 19-21 weeks for anatomy.

It can - but limited: The future trend will be to perform anatomical fetal surveys in the late first trimester (14 weeks) via transvaginal sonography. Expert centers in europe are already doing this successfully. In the U.S. Most practices perform the anatomy scan at 18-20 weeks to allow for pregnancy termination in case of serious anomalies. From an imaging standpoint, the optimal time is 24-28 weeks.