Cin 2&3 after second lletz.

Hi, this is my first time posting on here so I hope it all makes sense  

I went for my normal smear a year ago and my results came back abnormal with high grade severe dyskaryosis. I had a lletz procedure done 4 weeks later at my local hospital. The results from this lletz showed cin 1&2 but had clear margins and a good sample size. I then went for my follow up smear and got the same result as my first smear. I had another lletz procedure done within 2 weeks. I have just had my results back today and I now have cin 2&3. 

 
I am concerned about my results getting worse over the year and at the speed they are changing considering my first lletz had clear margins. 
 
I have 2 children already and wasn't really planning on having anymore but I am concerned about the effect the lletz treatment is having on my cervix and what happens if my next smear comes back abnormal. 
 
Has anyone else been in a similar situation and have any more information about why the cells are changing so quickly?
 
Thanks