Childless ladies like me have these unspeakable ideas after we watch our pals cooing over their youngsters. I’ve had sufficient now – moms will hate me however I’m going to inform the reality: SAMANTHA BRICK

I’m sitting in a Notting Hill cafe with my friend Erica who, at 32, is the same age as me. Over the past ten years we’ve been social partners in crime: we have shimmied on dance floors together, downed shots, snogged men in more countries than I care to remember.

Yet as I pour the pinot grigio into my glass, her hand immediately slides over the top of hers.

‘I’ve got something to tell you,’ she says. ‘I’m pregnant!’

Trying to hide my horror – the last time she had unprotected sex, muggins here had to organise the morning-after pill – my initial reaction was to ask who the father was and if she was keeping it. Thankfully, I reined myself in.

She immediately started gushing about how Ben, the barman she’d been hooking up with, was looking forward to becoming a father.

Really? I’d had bottles of fizz in my fridge for longer than they’d been seeing each other. And yet here was Erica, having seemingly undergone an overnight personality transplant. Soon she was patting her flat tummy, cooing over baby names and discussing the merits of various private maternity suites.

And so Erica joined the ranks of at least a dozen other friends of mine who, on announcing their pregnancy, all vanished from my orbit quicker than you can say Mumsnet.

Trust me, nothing changes decades-long friendships faster than a surprise pregnancy announcement.

Samantha Brick has ghosted friends who have become mothers. By her late 30s, she avoided pregnant friends because she was trying unsuccessfully to have a baby herself

This can be for various reasons.

In Erica’s case, we drifted apart because suddenly all she wanted to talk about was her textbook pregnancy, maternity leave rights and decorating the nursery (seemingly akin to the Palace of Versailles). If wanting to swerve all of that makes me a fair-weather friend then I’m guilty as charged.

(Incidentally, when I heard on the grapevine that she and Ben split two years later, I wasn’t surprised.)

Erica wasn’t the first – nor the last – pregnant friend to be ditched by me.

By the time I reached my late 30s, I avoided pregnant friends for entirely different reasons. Not because they bored me – but because they had everything I didn’t.

When I was between the ages of 37 and 42, my husband and I tried – unsuccessfully  for a baby of our own. This might seem a more socially acceptable reason to ditch your more fortunate friends.

Either way, I read Flora Gill’s piece last week on being ghosted by her friend as soon as she got pregnant with much sympathy – for her friend, that is, not for her.

Sorry Flora, but your wise friend knew perfectly well that you’d no longer be invested in your friendship and that motherhood would take over. In short, she dumped you before you dumped her.

And I get it. One pregnant friend of mine cancelled a night out two hours before meeting, not once but three times. My credit card secured the booking each time and, consequently, I was charged for the no-show. Did she ever offer to pay up? I think we all know the answer to that.

‘So many mothers demote friends who haven’t joined the baby club,’ writes Samantha Brick (picture posed by models)

Another friend insisted that now she was a mother she could only meet on weekdays in the daytime. Eh? I’d duly take a day off and stock up on healthy goodies, referring to the unrequested list of preferred foods for her (uncontrollable) toddler. Not only did the purees end up splattered across my coffee table and floor, they were smeared over my extremely patient dog, too.

We could never have an adult conversation – and at the time I was going through a divorce, so had a lot I needed to chat about. Every time her daughter interrupted us, whatever we were discussing was dropped so she could marvel over her child’s pronunciation of ’sausages’.

In both cases, I simply stopped calling them. Did they even notice I’d ghosted them? I do wonder.

That’s not to say I don’t have any friends with children.

My best friend is a mum of two and has always guarded our friendship – as have I. Throughout our almost 30-year relationship I’ve been on the phone with her at all hours when life hasn’t gone as planned.

And when she gave birth to her first son, I was the first in my car, driving hours to get a cuddle and make her go back to bed for some unbroken sleep. I was also the first person she told when she was pregnant with her second son.

She really took care of my feelings because, then aged 38, I was trying to become a mum myself. And, two decades on, I adore her grown-up boys and I’m the godmother of one of them.

She has rather brilliantly kept me a part of her sons’ lives. She recognised that childless friends are actually a mother’s secret weapon.

Keep us on side and we’re the ‘aunt’, godmother, girlfriend with one very large shoulder to cry on and a confidential, sympathetic ear for when things get too much for you.

So many mothers don’t clock this, instead demoting friends who haven’t joined the baby club and sidelining us at Christmas and on birthdays.

I live in France now, and it’s probably no surprise that my closest girlfriend here doesn’t have children. As cultured women who have seen the world, we have so much in common – similar tastes in books and a passion for our four-pawed families (she has rescue dogs like me).

We don’t spend hours talking about offspring. Our lives are richer for spending time with one another, not least because we don’t feel ‘othered’ when we’re with friends and the conversation inevitably turns to their children.

When a woman becomes a mother, of course her priorities change. But so do those of non-mums – and don’t be surprised if you’re cut out of our lives in the process.