After 35, the chances for a woman to conceive via artificial insemination are so low that the treatment of choice is usually in vitro fertilization.
So you can get an idea, while a woman in her 20s has a 20% of becoming pregnant during a unique menstrual cycle, by her mid-30s her chance would be about 15% per cycle. This rate continues to drop until menopause and, at age 40, it can be as low as 10%.
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