my wife miscarried years ago... early in the pregnancy. The doctor explained it by saying "God knows what is best".... and went on to explain that 2 out of 5 pregnancies end in a miscarriage, and that it's nearly always that something isn't developing properly, or some other major problem with the fetus. I finally saw what he was trying to say, and it actually made me feel better about the whole situation.
Next time will probably result in a wonderful new addition to the world, and your family.
Hug your wife a lot...