last pregnancy was high risk, and I was very anxious following a mc. by the time I had my 12 week scan i'd had 3 scans. After that I lose count, but probably one at about 16 weeks (worried about heavy discharge), my 20 week scan, then 24, then 26 as I had a bleed, 28 weeks, when growth was shown to have slowed, 30 weeks, 32, 2 at 33 weeks, 2 at 34, 2 at 35weeks and baby born at 35+5. The scans from 32 weeks were done by foetal medicine, and the decision to deliver early was made by them.
My first pregnancy I had the usual scans 12 and 20 weeks. An extra at 28 weeks to as I was measuring small, then 32 and 36 for growth, then one at 38+5 due to reduced movement. Baby born at 39+1, induced for low fluid and reduced movement.
I remember being very surprised at the big gap between appointments as suggested in my maternity notes. those appointments are what are suggested in a low risk pregnancy. I guess if they no longer think you are high risk the that's why you have a gap. If you have concerns you should be able to get an extra appointment or see your GP. Look out for the normal concerns (changed pattern of movements, bleeding, leaking fluid, sudden pain in legs or chest, difficulty breathing, excessive leg swelling and head aches). If these happen then you should get immediate attention, either at the GP, or to maternity triage or labour ward.