Hi CC,
I had a miscarriage earlier this year, then a few weeks later fell pregnant again. I too was very worried, but I didn't expect to receive an early scan or anything, just due to miscarriages being so common, and as sqad says, it won't prevent a miscarriage from occurring in the future.
Instead, I looked after myself as well as I could, did everything textbook, plenty of rest, minimise stress, avoided certain foods, extra vitamins etc. I accepted the miscarriage because like DT, I believe that it is nature's way of handling serious problems in the development of the baby, and just hoped that second time around, we would be more fortunate.
I did, however, buy a doppler, as I remember years ago when pregnant with my daughter, I hated the part between 12-20 weeks when morning sickness went, and I felt no movement, so it helped reassure me she was still there.