The other shoe

Unlike Shelley, who finds herself and her family to be uncannily lucky all the time, my family and I have a history of unluckiness. We are to the point where if things start to go well we perpetually wince in anticipation .... something's bound to go wrong.
Out family has been unlucky in employment, housing, choice of babysitters, driving, choice of stocks and investments, and frequently just being the wrong place at the wrong time. Thus we have encountered illegal work contracts, hidden stores of rat poison (discovered by toddlers), persons with extensive criminal records, propane explosions, ... oh you name it.
So.... it kind of makes me nervous when I go to each doctor's appointment and they tell me everything looks great. I almost want some small thing to go wrong so that nothing big can go wrong... if that makes any sense. Don't tell me everything is great! Tell me I need to get more calcium or something! I'd much rather have potentially brittle bones than have my baby born with some severe untreatable undiagnosable problem.
Maybe I just don't have enough faith that my body can do it right. It really doesn't seem possible that everything could come together just right to create a healthy baby. For example a part of me is certain that my baby will never get into the correct head-down position. How the heck would he know to do that anyway? Does every pregnant person feel like this? It's just too much of a miracle, I guess.