No ultrasound until 20 weeks?

So this is my first baby and I doctor in a smaller hospital in my hometown. I see the midwives and I like them a lot. But I have one problem, they told me I cannot have an ultrasound until my anatomy scan. Which I was put out at first, but I got over it. Well, I’m 14 weeks now and waiting patiently, until I see serval women who I am friends with that doctor in the same place I do, getting 12 weeks scans and some even earlier... they wouldn’t even schedule my first ob appointment until I was 11 weeks. I just feel like this is kind of odd that the women I know are being treated differently than I am. Maybe they have complications or conditions I am unaware of that would cause them to need one... I don’t know. Has anyone else ever been told they can’t have a scan until their anatomy scan? I’m just confused as to why so many women get scans earlier than that but my midwives say not until then for me.