I had a misscarriage twice, due to a blighted ovum, what could be causes and possible treatmen to avoid it happenning in future?

Hi,

I had Blighted Ovum twice, and the doctor's said it is jus by accident and could be a possible chromosomal error during egg formation time? While, I have got over the trauma, I want to get pregnant again. I dread the chances of another one, but I am searching for the treatment for this problem. I wish to know if a female's age and weight also play some role in this? I am 31 and slightly obese