Why do women that want kids stress about fertility decreases after their 20s?

according to my 2 minute research on the internet it says that women can still have kids past their 40s its just very low, it says the chances are a bit over 20% which means its still somewhat possible, i always thought they lost their full ability to reproduce after a certain age so i understood their stress but doesn't it being 20% just mean more sexual intimacy with their SO? is it really a bad thing? or am i missing something my male brain lacks the knowledge on? 🙂👂
Why do women that want kids stress about fertility decreases after their 20s?
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