For women 35 years of age, the miscarriage rate is 20 %; for those 40 years of age the rate surpasses 30 %; for women 45 years of age, the rate of miscarriage is already 50 %.
卅五歲時，流產率約二十％，四十歲時，就超過三成；到四十五歲流產機率已高達一半了。