How does religion explain birth defects?

[Cando]

Birth defects are part of life. It has nothing to do with religion. Anyone who can't undertand something as simple as that probably can't understand many other things, and should be spending their time actually learning rather than asking questions based on ignorance of the highest order.

Arrogance & ignorance all rolled up into one fairy-tale believing package.

But birth defects only affect a small proportion of the population.