The egg begins to break down after 24 hours after being released by the ovary at ovulation. During the female ovulation cycle, the egg is released anytime from day 8 to day 22 and not necessary on day 14. This depends on the length of the menstrual cycle, the length of the luteal phase and how fast estrogen levels rise. In fact high estrogen levels trigger the pituitary gland to release LH that stimulates ovulation. Women using a ovulation kit will look for the Lh surge to know that ovulation will occur in the next 12-24 hours. This is how long the life on an egg is.
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