This is such a tricky one to answer. I think a lot of it comes down to personal circumstances. I'm probably going to go against the grain here and say I don't see a problem with bigger age gaps, or people choosing to have children later in life for one reason or another.
I am the eldest of 5 and my youngest sibling is 22 years younger than me - Mum was 48 when she had the youngest. I was her birth partner and it was an absolute privilege to have been able to share such a special moment with her. So, with that in mind, I kind of always felt like 'too old' was more of a balance between what's biologically possible and how much you want it.
Over the last year, however, I found myself beginning to doubt that line of thinking, because what it doesn't really take into consideration is not just how you'd cope with pregnancy, childbirth and the early years, but also your health status and whether there is a reasonable degree of risk that you may not be there to see said child into early adulthood.
I know most of us don't really go about our days contemplating how long we've got on this earth (life would be pretty miserable if we did). However, my family were dealt a massive blow last year when we discovered that mum had pancreatic cancer. Despite best efforts to treat it, it is now likely terminal, which means she is unlikely to live beyond a year. She didn't have any hereditary gene mutations that would have explained why, at the relatively young age of 60, this had happened. There were no warning signs. It was just 'bad luck'.
In simple terms, my youngest sibling is now facing the terrible prospect that she will have to navigate life from her early teen years without her Mum. And I'm fairly sure I don't need to tell you what an agonising burden that is, for all involved.
Realistically, I know anything could happen at any given moment, and we make the best decisions we can based on our circumstances in the here and now. But I have to say that recent life events have certainly given me pause for thought on this particular topic.