When are parents going to realise that having a child is a gamble. There are no guarantees. Like with every decision you make in life, you make the best guess that you can and prepare as well as you can, then roll the dice and deal with the outcome as best you can.
Gattaca, anyone? "I'll take.. hmm..blue eyes, blonde hair, strong physique and extremely intelegent please" "Yes, Mr. Hitler." Or, the majority of Pakistan, India, China, Japan etc: ".. male..."