India, Aug. 29 -- Birds do it, bees do it, even educated fleas do it. And yet, across cultures and through human history, pregnancy and fertility have inspired a remarkable range of beliefs, rituals and superstitions.

And why not? What thinking species wouldn't be amazed at the idea of new people simply appearing as if from thin air?

These traditions have sought to explain conception, influence the sex or health of the child, protect women during pregnancy and childbirth. Today, they provide deep insight into how different societies have understood birth and reproduction.

At traditional Chinese weddings, for instance, a red umbrella is used as benediction. An elderly woman whose family extends to sons and grandsons is appointed as "goo...