In some versions of the Japanese creation myth the jumbled mass of elements at the beginning of time was in the shape of an egg. Later in the story birth also comes into play because Izanami gave birth to her children who became the sun and moon.
At the beginning of the Greek myth the bird, Nyx, laid an egg. From this egg comes the god of love, Eros. Then the shell pieces became Gaia and Uranus, the Earth and sky. Again the egg is very important.
The Iroquois Sky Woman fell from the floating island in the sky after being pushed by her husband. This all occurred because she was pregnant. If she had not known she was to give birth North America may not have been created. It was an essential part of the story.