Usually, when they do karyotyping and the results come back with Trisomy, they send you to a genetic counselor.
I am no expert. But, from what I have read, 60% of all mc's are caused by Trisomy, the bulk being Trisomy 16. It is caused from a problem during cell division. It is not normally caused from the parents. But, just an anomaly. The likelyhood of a 2nd pregnancy resulting the same is about 1%.
If, and that is a big if, it happens again, they test the parents for a marker that may be the cause. But, most all cases are not from the parents. Here is a link that may help. It's a little long and in some parts technical.
I am sorry this happened and wish you a successful 2nd attempt. Also, 6 mos is about average for normal healthy couples. Don't blame yourselves for what happened. It is not your fault.
Hello I had just read your post. I had a MC at 8-weeks and it only took us 4-months to conceive the 2nd IUI took. I had my results sent to a genetic test and came back a month later and it was accidentail thing that happened. My fertility is good my husband has no sperm so we are using donar sperm. Anyways basicially how my rE explained it was during cell division which there is no way of monitoring me or checking. They are confident that I will get pregnant again when I am ready and wasnt concerned. I wouldnt be concerned about it as she said it could of happend to anyone anytime under any circumstances. I was relieved thinking I did something wrong but was perfectly fine. I will check out the article as sounds interesting to read on as well. Good luck