Does Elevated Thyroid Levels Cause Miscarriage?

I just miscarried identical twins at 10 weeks (April 2010). I went in for a standard check and no heart beat was detected, despite healthy heart beats of 124 and 125 at 6 weeks. Based on the twins' measurements, my obstetrician though they had continued to grow up until that day (ie. they had only just died). Otherwise, I had had no symptoms of miscarriage. As you can imagine I am devastated.

I had a blighted ovum last August, so my doctor had all the usual tests done for potential causes of recurrent miscarriage, including hormonal and genetic testing. My tests came back revealing elevated thyroid hormone levels. I will go in for further testing in a few weeks. I understand that thyroid levels can be responsible for miscarriage.

I am feeling terribly guilty. Before I knew I was pregnant (my husband and I were not trying), I had one treatment of mesotherapy (about 4/5 days after conception). Interestingly I think the egg would have split (for twins) very soon after receiving the mesotherapy treatment and I wonder if it may have been a contributing factor. As soon as I found out I was pregnant, I told my doctor I'd had mesotherapy and having considered the ingredients, he didn't think it would be a problem with the pregnancy, as long as I didn't continue any further treatments (which of course I did not).

Now I am learning that lecithin (a soy based product contained in mesotherapy) can be responsible for raising thyroid levels and in some cases even cause thyroidtoxicosis. I am wondering if the mesotherapy taken some 6 weeks before the miscarriage, might have caused it.