I know a few people who have been dealing with balanced translocations whilst TTC. I'm not sure what the odds of a successful pregnancy are. I'm pretty sure it's 25% normal, 25% balanced translocation and 50% unbalanced translocation (which would end in mc). That would be something to talk to a geneticist about.

A genetic defect isn't anyone's "fault", it's just the roll of the dice. I'd want to know either way, so as to understand the likelihood of successful conception. Whilst there is the option of IVF/PGD, it is expensive and you're then dealing with the risks of IVF (egg harvest, fertilisation, PGD testing etc.) One option is a CVS, but I think most unbalanced translocations miscarry before then.

Maybe ask in the IVF PGD thread for experiences.

As for blighted ovums, there are a number of reasons they occur including damage to egg, sperm and the initial blastocyst.