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What happens when an egg is not fertilized?
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menstruation
Cyclical changes during a woman's normal ovulatory menstrual cycle.
When an egg is not fertilized, the following biological process occurs:
- Degeneration of the Egg: If the egg is not fertilized within approximately 24 hours of its release during ovulation, it begins to degenerate.1
- Luteolysis: The corpus luteumāthe structure formed from the ruptured follicleābecomes inactive after 10ā14 days and eventually degenerates.23
- Hormonal Withdrawal: As the corpus luteum degenerates, it ceases the production of estrogen and progesterone. The resulting drop in these hormone levels triggers a spasm in the endometrium's blood vessels.43
- Menstruation: Deprived of oxygen and nutrients, most of the endometrial lining dies and is shed along with some blood, resulting in menstruation. This discharge marks the end of one menstrual cycle and the beginning of the next.43