I agree that it is important to look at the statistics: there's no arguing with biology.
However, NO set of numbers can predict what is going to happen to an individual. For instance, I had 3 consecutive MCs first and then had 2 babies, so was obviously older.
Also re genetic risk: yes, trisomy risk rise with maternal age (some also with paternal age) and a risk of, say, 1:18 sounds very, very scare when compared to somebody else's 1:3000 risk, but it still means that 17 out of 18 babies will be unaffected.
Re fertility: nobody knows what their fertility is like until they try it out
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I think that nowadays it is less common to actively TTC in your 40s (although getting more common again) than it was before the advent of reliable contraception (it was fairly standard for women to have pregnancies form their late teens in to their late 40s not that long ago).
It's always a lottery, and IMO you either go for it, or you don't. There's not much in-between.