Ultrasound Feedback

Dear Jesica,

Here's another useful 1st trimester u/s application. I'll be 35 when I deliver this spring, technically "advanced maternal age" (ha!), so my midwife at UCSF in SF recommended this new diagnostic
test that can be done earlier and is non-invasive when compared with
the standard CVS and amnio tests.

I personally prefer to have as few ultrasounds as possible, but having
one early on with the end result of avoiding the CVS and/or amnio test
was well worth it in my book.

But I definitely don't understand the OBs who do them everytime a woman
comes in for a routine appointment, just so they can "see" the baby.
That just seems excessive to say the least! Love your blog by the way! - JJ

Dear JJ -

This type of ultrasound is a screening tool that is a definite improvement over the Quad Screen - it is more accurate and can be done earlier.

However, it is important to remember that this type of ultrasound is still a screening test, not a diagnostic test. An accuracy rate of 87% means that 13% of Downs babies still will not show with this test. Likewise, the 5% false positive rate means that out of 100 mothers who this test indicates Downs for their babies, 5 of those babies will not have Downs.

The only way to know for sure is still amniocentesis...and it still carries the 1 in 300 risk of miscarriage. Both screening and diagnostic tests can be great tools if the mothers choosing to have them 1) want the information, 2) understand the limits of the information they will receive, and 3) understand the risks or possible risks with obtaining that information.

Thanks for the article!

PS - The blog loves you too! :)