I declined all testing and had an out of hospital birth where we discovered baby has a birth defect. We both almost died. My dds disability could not be detected on an us but my whole world came crashing down that night. We were so shocked, it was so hard to come to terms with on top of all the chaos of transferring and emergency care.
My reason for declining testing (only a 13 wk us was offered, no 20 wk was covered!) was that we wouldn't terminate the pregnancy if for example there were downs markers. My experience made me realize that I could have had months to come to terms with a special needs child rather than the cold hard slap in the face that I had after my 27 hour labor. False positives exist but id rather have a happy surprise than the one I had.