female menstruation

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…is unusual. In terms of conception, fertility depends on three factors: a healthy egg, healthy sperm, and favorable cervical mucus. A woman ovulates once a cycle. The egg lives twelve to twenty-four hours and then disintegrates if not fertilized. Under favorable cervical mucus conditions (cervical mucus nourishes and guides the sperm, which would otherwise die in about a half-hour or never reach the egg), sperm can survive as long as five days within the body.