Trying preseed but scared of miscarriage

I'm going to try preseed this month but I'm scared of miscarry ing if it gets me pregnant. I've been trying for over a year and I'm nervous that when I finally get pregnant I will miscarry. I know preseed doesn't cause miscarriages, but I have heard that the lubricant helps along the sperm that isn't 'great' quality if that makes sense? Which can possibly cause a miscarriage ? Just a bit nervous. How do I get this worry out of my head?