Etopic pregnancies

So over here in the UK we go for our first scan at 12 weeks unless there's been complications in the past ect , I know that in the USA you guys pay for them so you can get them whenever you want a early as you please really since you do pay for them. My question is why don't we get scans a bit earlier on to check for etopic pregnancies so that the woman can get the proper care that they need? I'm assuming by 12 weeks the baby would rupture the fallopian tube or by then sadly pass on causing a mc. I'd love to know peoples opinions of it . maybe I'm not educated enough on the subject.