TODAY THE GCSE results are announced, and it seems almost inevitable that girls will again, as they did in A levels last week, widen their lead on boys in the higher grades. And yet the puzzle remains, that the young women who worked so hard to receive those A and Bs will, once in the real world, fail to make hoped-for progress in pay and promotion.

What is news though — front-page news, ladies and gentlemen — is that I have had a baby. Not only has this unprecedented event in history oc-curred, but I have been thinking about it a lot. On the wrong side of 3am even bits of half-remembered poetry seep into your brain, and that is when, suddenly, I stared down into the inky eyes of my newborn girl and did not know whether to be angry or sad.

I realised there is an overlooked cause of girls’ underperformance after they leave education: the very excess of concern that helped them to clock up such good grades. The fears of mothers and — perhaps especially — fathers pull daughters back from brilliance. There is safety of numbers in the middle: being at the edge — well, as every parent knows, children fall off edges. Good girls do well in school, yes, but in the scary outside world, average is safe.

There are all sorts of biological theories as to why girls do not make good on their early promise, such as women are more naturally inclined towards family, or are naturally less aggressive, but a common refrain is how the female tends towards the middle. Several studies have, controversially, plotted this in terms of IQ, showing that men’s average intelligence may be only a few points ahead of women’s, but women’s scores are much of a muchness.

The stupidest person in the world is probably a man, but so is the cleverest. This kind of pattern is often repeated in the animal kingdom, with males showing much greater variations in patterns and so on, perhaps as a way of keeping some biodiversity. There is even a suggestion that the success of girls is proof that exams are getting easier: A now stands for average.

Amid all this genetic determinism no one thought to consult Philip Larkin. Born Yesterday, the poem he wrote to celebrate the new baby of his great friend Kingsley Amis, used to be a favourite of mine. “May you be dull,” he writes, if that is what an “unemphasised catching of happiness” is called, and I nodded along, until that 3am morning. Then it occurred to me, with a start, that Larkin did not wish dullness on all babies, but specifically Amis’s daughter, Sally, whom he wanted to have “like other women, an average of talents”. This is hardly a case of Shakespeare’s sister, but when Kingsley’s son, Martin, was born, Larkin did not wish for him to “be ordinary”; and indeed, he has not turned out to be so.

Rereading it in this light, I find the poem more unsettling — and true. The first half invokes Sleeping Beauty, in which, if you have not been to panto recently, fairy godmothers cluster round the crib of the cherished princess, wishing great things for the girl. There is something terribly unlucky about this, and soon enough the wicked fairy puts a curse on Sleeping Beauty. Larkin also distrusts a surfeit of blessings, telling Sally that being exceptional will “ pull you off your balance”.

The predecessor of Born Yesterday is another poem written to a baby girl, W. B. Yeats’s A Prayer for My Daughter. As a terrible storm rages through the night, Yeats paces the room around his daughter. who is somehow managing to sleep through the noise. All his thoughts are for her safety, and he wants to guarantee this by making sure she does not overreach herself. “May she be granted beauty and yet not/ Beauty to make a stranger’s eye distraught,” he frets; nothing she has should be “overmuch”. “Fine women”, he writes,“eat a crazy salad with their meat.” Don’t doom your daughter by expecting too much.

There is no female Icarus (her parents thought it would be too risky for her to experiment with hot wax and feathers) but it is worth mentioning the brilliant Sylvia Plath. Somehow she seemed to have to pay for her extraordinary poetic talent with an untimely death.

Father-daughter poetry is interesting in its own right, from Shakespeare to T. S. Eliot, and it is usually touching in its emphasis on safety (Prospero shushing his feisty daughter Miranda by bewitching her to sleep: “tis a good dullness”). Maybe there is a genetic factor that makes it harder for women to reach the pinnacles of human endeavour. But we will only really be able to tell once poets start writing odes to their sons, warning them that they are too frail to be tall poppies.

A few months ago I awoke from the lurid dreams of the sleep-deprived and found the flat eerily quiet. Stumbling into the bedroom, I made out the lump of a tightly bound baby in the cot, and the grey outline of her father sitting alongside. He was quiet and slumped as he stared into her basket.

“I was just thinking about what she’s going to be when she grows up,” he whispered. “It made me realise for the first time how hard it is to achieve something as a woman.”

I joined him staring into the cot, thought of Larkin, Yeats and those fairy godmothers, and felt very torn. Do I dare wish her anything other than ordinary?

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