Ultrasounds at 20 weeks

Hi Ladies, I have a question. How many ultrasounds have you had by week 20? I live in NJ and I'm a little concern about the attention I'm getting from my doctor. He only did one ultrasound when I was 8 weeks. I have seen him every month ever since. He only checks my baby's heartbeat. He has the equipment at his office, so I don't see why he wouldn't do any more. For my anatomy scan he sent me to a specialist who was really nice, we found out we are having a girl but all the photos that we got were just my baby's body parts. I see a lot of you ladies having nice profile photos and 3D photos and I'm wondering what my doctor is waiting for 😔😔