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Egg donation - for donors |
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Won't the treatment make me run out of eggs?
Women are born with around two million eggs which die off as time goes on. By the age of her first period, the average woman has 30,000 eggs left.
The part of the ovary that produces an egg is called a follicle. Every month a small number of 'resting follicles' in each ovary are triggered to develop. Most of these can potentially produce an egg, but normally only the strongest will continue to grow, while the others die away. Medical intervention ensures that all the available growing follicles develop to a point where they can produce a mature egg, and ovulation is stimulated by an injection.
It isn't clear why some follicles develop and some simply atrophy without ever growing. It isn't straightforwardly related to the menstrual cycle - follicles die even when a woman is pregnant. But there is a relationship between fertility levels, hormone levels (and the hormone balance) and the number of eggs a woman has left. This is why the clinic will test your hormone levels during your cycle, as it helps to determine how fertile you are.
Menopause occurs when the ovaries run out of follicles. The average age of the menopause in the UK is 50, but for a woman to produce healthy eggs she needs to be much younger. There is no evidence so far to suggest that the drug treatment triggers the menopause for donors or IVF patients any earlier than it would have happened naturally.
More detailed information can be found on the website of the Advanced Fertility Centre of Chicago.
January 2005
