I wondered whether you would say they were less than 8 weeks, a blighted ovum cannot be truely diagnosed before this point. So the 6 week miscarriage would not be considered a blighted ovum as women with a tilted uterus have scanned that can be upto 2 weeks behind and so it is not possible to say that there was definitely no feotus at this point. It can only be diagnosed as a blighted ovum when the sac gets big enough to truely show that there is no embryo, this is normally confirmed at around 10 weeks, sometimes as early at 8 weeks, but due to women with tilted uterus' this is sometimes a misdiagnosis.
I have children and since then 9 miscarriages, and nothing found until I did clotting tests when I was pregnant. I had normal tests when not pregnant.
This has meant I am now on a new treatment regime.
You 6 week miscarriage, may have been just one of those things rather than a blighted ovum and so it might have been completely random (the 1 in 4 statistic). It does not make it much easier for you, but it might help to think that the statistics for miscarriage do not increase signigicantly until after you have had 3.
I am trying to encourage you that there is a good chance that if you got pregnant again, that all could be ok.
As are recurrent miscarrier I fully understand your worries. If you want other routes to look down other than the routine testing done, you could consider looking at NKcell testing, done in a few places the main guy being Dr Shantala. Several women on the miscarriage threads have gone down this route.
There is also the TEG test (that picked up my issue of clotting in pregnancy) done at St Mary's.
There is also the double blind trial results due to come out later this year on prednislone for recurrent miscarriage.
I know it is hard facing another chance of m/c, and sometimes it helps doing further investigations. Sometimes it does not help. So really it is up to you to think about what would help you the most.
I hope you get your babe in arms in the near future.