My View: Parenthood is better for children the

Any woman whose fertility has been taken away must wonder what might have been, if she had accidentally fallen pregnant when younger, possibly remembering early pregnancy scares with bitter irony. I know I would have done.

So perhaps it's not surprising that this week Hilary Mantel has stepped into the teenage motherhood debate by suggesting that girls are ready to have babies at 14. "I was perfectly capable of setting up and running a home when I was 14," she said, adding: "And if, say, it has been ordered differently, I might have thought 'Now is the time to have a couple of children and when I am 30 I will go back and get my PhD'."

If Hilary Mantel says she was capable of all this, maybe she was capable. Maybe other teenage girls are capable, too, although none that I know. When I was 14, I wasn't capable of taking a mug to the kitchen or deciding which member of Spandau Ballet I fancied most, let alone running a home and bringing up a couple of children – children who, by my reckoning, might have been 16 and 14 by the time I was 30.

Now, as the frazzled mother of a 15 and a 12-year-old, I laugh mirthlessly at the prospect of finding either the time or the brain cells required for a PhD, because I'm not sure I could pass Year 2 Sats after 15 years of motherhood. This much I know – and yes, I am blessed for that.

Parenthood is better for children the later you leave it, which is why I am far less concerned about 58-year-old women being given IVF than I am about teenagers having babies. The 20s is too young to enter parenthood, too, in general, although there are 20-something mums and dads who do a sound job. But couples in their 20s are often too wrapped up in working each other out to be able to give children the unconditional love, time and patience they need. Patience is not just a virtue, it's a downright essential for parenthood, and it's something that develops with age. It's a sad quirk of nature that, in her mid to late 30s, just as a woman has developed the life skills she needs to cope with having children, her fertility begins to wane.

In Giving Up the Ghost, Mantel writes of the ghosts of children who would never exist: "When you think you're pregnant, and you're not, what happens to the child that has already formed in your mind?"

There's no right time to have a child, and perhaps there's no wrong time either. But there are times that are better than others, and that's when you have not just security but also enough love, patience and wisdom to spare.