You've bonded with a new acquaintance over books and films and nightmare bosses. Then she leans forward and asks: "Do you have children?" You compose your expression. Try not to rush the answer or sound brusque. "No, I don't actually." Then you smile – warm, but neutral – and move the topic on.
It still surprises me that people lob that question into conversation with a near-stranger. Don't get me wrong, it's a good question, but it's an intimate one; one that requires the context that only real friendship brings.
Being "child-free" is not the great tragedy in my life. I travel a lot. I have fantastic friends. In my spare time I've written a couple of books. I live with three unruly cats.
Yet I'm also part of a growing trend. One in five Irish women over 45 is now childless. A new OECD study revealed that women in Ireland have the fourth highest rate of childlessness in the developed world (after Italy, Austria and Britain).
The child-free are no longer a strange aberration, pitied by society. In fact, 43pc of university-educated women from Generation X (born from the early 1960s to the early 1980s) remain childless.
Sometimes, it surprises me. How did I manage to avoid the template that is laid out so clearly for women? Maybe it's that time has a habit of slipping away while the drama is going on elsewhere.
Looking back, in my relationships I was drawn to creative, depressive men. My father suffered anxiety attacks throughout my childhood so it was something I knew quite a lot about.
Maybe it brought out the rescuer in me, but I also hoped that partners would be open-minded about my own baggage (memo to self: it doesn't automatically work out that way). It was hard enough getting them to book theatre tickets, so the whole issue of children barely arose. Sometimes I wonder just how I avoided The Talk for so many years.
I'm not the only one. Few people make an early, irrevocable decision not to have children. Another new study found that up to 40pc of women surveyed had either not talked to their partner about having children, or only discussed it once, early in their relationship.
According to Edina Kurdi of Middlesex University, who led the research: "One possible reason that couples did not need to talk about the issue much is they could accurately sense their partner did not want children from their beliefs and lifestyle." Spoiler alert: if you meet a man hang-gliding, it's a fairly good clue he's not buying a Bugaboo pushchair any time soon.
The OECD study highlights issues that make it harder for couples to begin family life: it takes a long time to get on the housing ladder even with a professional job; there's a lack of affordable childcare.
Many women delay having children until they feel more secure to take maternity leave; others haven't met a significant other likely to make a good co-parent (dubbed "social infertility").
There are brilliant, independent women, such as Helen Mirren, Marie Helvin and the historian Lucy Worsley, who chose not to have children. As the first economically independent generation of women, we have better access to jobs, finance, sexual health, contraception.
Worsley created a furore when she joked: "I have been educated out of the natural reproductive function. I get to spend my time doing things I enjoy. I don't think my life is wasted." But many happily coupled people do put their lover, job, freedom first. And hurrah to that.
There are also people for whom the whole topic of infertility is fraught with pain. And not just women; I always loved the late (childless) novelist Iain Banks for saying that if you saw him cooing like a loon, it was over a baby in a pram or a new car.
Accepting that you will have a different path takes resilience, but for me the most intriguing fact that emerged from the studies is that being childless has little impact on happiness in the long-term. It's still possible to have a good life.
A study of families in the US found that no group of parents, whether married, single, step or empty-nesters, reported significantly greater emotional wellbeing than adults with no children. In contrast, other factors such as not having a job or friends did have a major impact.
In essence, a child brings huge joy, but it also brings anxiety about the future, which pretty much cancels out the joy. Pets, on the other hand, are truly emotionally rewarding.
It helped that I never felt that gnawing baby hunger.
In my thirties, I was busy trying to carve out a freelance career – it seemed like I had years to decide. And the social life was excellent.
People without children – gay, straight, coupled or uncoupled – hang out together.
And we're always hiring new people.
By the age of 40, I realised that if I wanted to have a child I needed to do it fast. I looked hard at my character and realised that I didn't have the resources, emotional or psychological, to do it on my own.
I knew I'd be on the margins of life as a single parent. Most of my friends are child-free.
Did I really want to pull down the life that I'd carefully assembled, brick by brick? I realised what I craved was more companionship, sex, travel.
And, of course, there are the politics.
We were brought up to be feminists by mothers who had their babies in their early twenties. Many were forced to give up their careers. They didn't want that for us and neither did we.
When I think about the two boyfriends who did "suggest" marriage, I feel sad. We were far too chaotic and mixed-up to pull it off in our thirties.
They both died before the age of 45. So when I mourn, it's not because we didn't have children, but because they didn't have more life.
At this age, we all have different, valid projects. I am fascinated by my friends who have kids. I want to know more about what it's like being a parent. I hate the way employers encourage single people to moan about mothers leaving work on time when I know they've been in since 8am, and never arrive with a hangover. But I'd ask for a little courtesy in return. Go gently when you ask anyone about their "child-free" status.
"I feel relatively OK about being childless now," a friend observes. "But marvel how freakish I feel at work when colleagues announce pregnancies. I don't know how people make me feel like this – it's all in the unsaid."
It's true the child-free develop an antennae for disapproval. I'm sorry, but we do get more party invites (and did I mention the sleep?). Arguably society benefits from a cohort of skilled, educated women who pour their energy into work. It's no coincidence that 45-plus women have a portfolio career.
I was sad when my last relationship ended, but I have faith that there will be more fun. I have an extended "para-family" of friends.
And conscious uncoupling is easier without kids.
Dating again is never a dream, but having been through the fire and made my grown-up decision about children brings its own peace. My heart goes out to 38-year-old women still in the thick of it.
More and more I'd like to volunteer or mentor, as it's unhealthy to hang out exclusively with your own age group.
I also think it's bad for society that we increasingly fall into two tribes, parents and non-parents.
Nobody wins if we regard each other with hostility and suspicion. Let's listen to each other's stories with tact and sympathy – there are many ways of being a family in the 21st century.
For some, the whole topic of infertility is fraught with pain. Being a parent is tough but rewarding. It was not for me.