36 weeks is when i had one

They usually just do one around 20 weeks and that's it. I requested one after I was 34 so my doctor did one but they don't usually do one in the 3rd trimester unless there's some complications . And after I requested it they had found that baby was actually measuring way too big so now I have one every week until baby is here

Depends on the dr really. You can always request an ultrasound but you would be required to pay for it since it’s not a medical need.

My last one was at 20 weeks...I didn't know they did a 3rd trimester one unless you had complications.